Season 1 Episode 2
Conclusion. The legendary wizard sets out to raise young Arthur as a true and noble man, hoping to bring peace and harmony to the land - but reckons without scheming Queen Mab's interference and her influence on Morgan Le Fey. Sam Neill, Miranda Richardson, Helena Bonham Carter, Isabella Rossellini, Jason Done and Martin Short star

 
Season 1 Episode 3
The Mark of Nimueh A witch poisons Camelot's water supply, sending a terrible sickness through the kingdom. Merlin ignores Gaius's warnings against practising magic and uses it to alleviate Gwen's father's illness, but his actions place the girl's life in danger. Michelle Ryan guest stars alongside Colin Morgan

 
Season 1 Episode 4
The Poisoned Chalice Bayard and the knights of the Western Isles arrive in Camelot for a feast celebrating a union between the two kingdoms. Nimueh poses as a serving girl and infiltrates the festivities with a view to gaining revenge on Merlin, poisoning the warlock and sending him into a coma. Clive Russell guest stars

 
Season 1 Episode 5
Lancelot Lancelot arrives in Camelot and leaps to Merlin's rescue when he is attacked by a griffin. The warlock learns of the aspiring knight's lack of nobility and fabricates credentials to help his new friend achieve his ambition. However, the ruse is uncovered and Lancelot is thrown in jail. Former Heroes star Santiago Cabrera guests

 
Season 1 Episode 6
A Remedy to Cure All Ills Morgana succumbs to a mysterious illness and a new physician arrives in Camelot just in time to cure her. Uther is impressed by the stranger's abilities but Gaius becomes suspicious and enlists the help of his friend Geoffrey of Monmouth to find out more about the newcomer. Guest starring Green Wing's Julian Rhind-Tutt and former Grange Hill actor Michael Cronin

 
Season 1 Episode 7
The Gates of Avalon Arthur and Merlin are hunting in the forest when they rescue a man and his beautiful daughter from bandits. The prince is besotted with the girl and offers the pair refuge in Camelot - unaware the object of his affections poses a threat to his life. Guest starring Kenneth Cranham

 
Season 1 Episode 8
The Beginning of the End A druid and his boy apprentice are discovered in Camelot and try to avoid capture. The elder is caught and executed, but Merlin hears the juvenile's telepathic cries for help. Despite the Great Dragon's warnings to be wary, Merlin risks his life to protect the youngster, putting Arthur in danger

 
Season 1 Episode 9
Excalibur Arthur's uncle Tristan De Bois returns from the grave in the form of a mysterious knight in black. Although intent on revenge for his sister's death, he could also reveal a secret from Uther's past. Gaius realises the only way he can be killed is with a sword forged in dragon's breath. Featuring the voice of Christopher Fairbank

 
Season 1 Episode 10
The Moment of Truth Bandits attack Merlin's home village, where his mother Hunith still lives - but with Uther unwilling to provoke a war by crossing the border to repel them, Arthur joins forces with Morgana and Gwen. However, an old friend of the wizard's, William, accuses Arthur of provoking the situation. Alexander Siddig and Joe Dempsie guest star

 
Season 1 Episode 11
The Labyrinth of Gedref After Arthur kills a unicorn while hunting, Camelot's crops are destroyed and its water supply runs dry. The prince refuses to believe he could be responsible for any curse, but is warned by the animal's keeper that he must make amends or the kingdom will face ruin. Frank Finlay guest stars

 
Season 1 Episode 12
To Kill the King Gwen's father Tom is put on trial by Uther, accused of practising magic by helping a sorcerer turn lead into gold. However, Morgana fears his fate has already been decided, and tries to help him escape before he is sentenced to death. Cal Macaninch guest stars

 
Season 1 Episode 13
Le Morte d'Arthur Arthur is mortally wounded by a monster that has the body of a lion and the head of a serpent. Merlin seeks out followers of an ancient religion who have the power to reverse death, but he faces a tough decision after learning that another life must be sacrificed for the prince to survive. Last in the series

 
Season 2 Episode 1
The Curse of Cornelius Sigan Colin Morgan returns as the talented young wizard to protect Camelot from a fresh batch of foes. When slippery servant Cedric starts causing trouble, Merlin discovers the newcomer is a conman who hopes to get his hands on a precious jewel recently unearthed from a tomb. But without the support of Arthur, Merlin has to find help from the creature he swore never to trust again - the Great Dragon. Mackenzie Crook guest stars, with Bradley James

 
Season 2 Episode 2
The Once and Future Queen Worried that the knights will let him win because of who he is, Arthur enters Camelot's jousting competition anonymously. Though he struggles to adapt to living undercover at Gwen's house without the privileges of rank, the prince is so determined to prove he can do it that he fails to spot the danger from a bounty hunter sent to kill him. Fantasy drama, guest starring Adrian Lester, with Bradley James and Angel Coulby

 
Season 2 Episode 3
The Nightmare Begins Morgana begins to wonder whether she has magic powers, but Gaius insists she remain ignorant of her potential for her own good. Merlin refuses to accept the decision, and in wilfully disobeying his master, he reunites Morgana with Mordred, the boy the Dragon predicts will one day kill Arthur. Drama, starring Katie McGrath, Richard Wilson and Colin Morgan, with Colin Salmon

 
Season 2 Episode 4
Lancelot and Guinevere Gwen is mistaken for Morgana and kidnapped by savage outlaw Hengist, prompting Arthur to defy his father and race into enemy territory to her rescue. However, he finds she is not alone in the abductor's castle - Lancelot is already there. Fantasy drama, starring Angel Coulby, Bradley James and Santiago Cabrera

 
Season 2 Episode 5
Beauty and the Beast - Part One Part one of two. Uther becomes infatuated with the beautiful Lady Catrina, a newcomer to Camelot. However, Merlin realises she is really a troll hiding her true identity behind magic. As the young wizard fights to prove to the disbelieving Arthur that the woman is a monster, it becomes clear she is motivated by more than the prospect of winning the king's heart. Fantasy drama, guest starring Sarah Parish and Adam Godley

 
Season 2 Episode 6
Beauty and the Beast - Part Two Part two of two. Having married Uther, Queen Catrina increases her influence over Camelot. Her accusation that Merlin is a thief forces the wizard into hiding, leaving him to seek evidence that she is secretly a troll. If that were not hard enough, he must also identify the spell that will break her hold over the king. Fantasy drama, starring Colin Morgan and Anthony Head, with Sarah Parish and Adam Godley

 
Season 2 Episode 7
The Witchfinder Uther invites notorious witch-hunter Aredian to Camelot in a desperate bid to rid the kingdom of magic, and no one is beyond his suspicion. Morgana is certain the ruthless detective will burn her at the stake, so it is up to Merlin to try to save her without landing himself in trouble. Fantasy drama, guest starring Charles Dance, with Anthony Head and Colin Morgan

 
Season 2 Episode 10
Sweet Dreams Dignitaries from rival kingdoms visit Camelot for peace talks, but one monarch, King Alined, hopes to stir up war by using magic to bewitch Arthur into falling in love with Vivian, the daughter of King Olaf. As the prince grows besotted, chaos reigns and it seems inevitable that the lands will be pitched into conflict. Guest starring Georgia Moffett and Mark Lewis Jones, with Bradley James

 
Season 2 Episode 11
The Witch's Quickening A ruthless warlock sends Mordred to steal a priceless magical relic Uther has locked deep within Camelot's vaults, relying on Morgana's bond with the boy to keep him safe on his mission. Though many have died trying to get their hands on the Crystal of Neahtid in the past, the true power of the ancient artefact is beyond even Merlin's imagination. Joseph Mawle (Jesus in The Passion) guest stars, with Katie McGrath

 
Season 2 Episode 12
The Fires of Idirsholas Fearing the revival of the deadly Knights of Medhir after 300 years, Arthur and Merlin leave Camelot to fight the magical army. In their absence an enchantment is cast that subdues the whole population except Morgana, and Morgause returns to the all-but-defenceless city - more determined than ever to destroy Uther. Starring Emilia Fox, Bradley James, Colin Morgan and Katie McGrath

 
Season 2 Episode 13
The Last Dragonlord The Great Dragon is finally free and, in its mighty rage, attacks Camelot. With the castle crumbling, the knights cannot hold out much longer - only a Dragonlord can kill such a beast and Uther wiped them all out years ago - or so it is believed. Gaius reveals one such man may still be alive and in hiding, so Arthur and Merlin set out in search of him, before the kingdom is destroyed. But even if they find him, can they persuade him to help his old enemy Uther? Colin Morgan, Bradley James, Richard Wilson and Anthony Head star, with a guest appearance by John Lynch. Last in the series

 
Season 3 Episode 1
The Tears of Uther Pendragon A year after her disappearance, Morgana returns to Camelot, where a delighted Uther immediately announces a banquet in her honour. However, when evil magic begins to take hold of the king's mind, Merlin suspects the lady is hiding a sinister secret, only for the wizard's search for the truth to leave him at the mercy of the scorpion-like enchanted serkets. Colin Morgan and Katie McGrath star

 
Season 3 Episode 2
The Tears of Uther Pendragon - Part Two Part two of two. Following continued manipulation from Morgause, Cenred launches an attack on the citadel that places the fate of Camelot on Arthur's shoulders - but the initially strong counter-attack is overwhelmed when Morgana uses the enchanted rowan staff given to her by Morgause to summon a skeleton army from the vaults beneath the castle. Merlin hopes to put an end to the battle by stopping Morgana and vanquishing the enemy within - but must achieve his goal without revealing his magical powers. Adventure, starring Colin Morgan and Bradley James

 
Season 3 Episode 3
Goblin's Gold After stumbling across a secret chamber, the young wizard accidentally releases a goblin - and there is chaos in Camelot when the mischievous creature possesses Gaius. Uther suddenly turns bald and the royal family starts suffering from terrible bouts of flatulence. With the monster running riot, Merlin races to solve the problem before any more damage is done. Colin Morgan and Richard Wilson star, with The Fast Show's Mark Williams as the voice of the goblin

 
Season 3 Episode 4
Gwaine An enigmatic young man steps in to help Merlin and Arthur when they find themselves outnumbered in a tavern brawl. Risking his life to protect the prince, the stranger is seriously wounded and taken back to Camelot, where he quickly makes a recovery and begins drinking, charming the ladies and causing trouble for Merlin. Guest starring Eoin Macken

 
Season 3 Episode 5
The Crystal Cave The wizard has an unexpected meeting with mysterious old sorcerer Taliesin, who takes him to the crystal cave and shows him a glimpse of the future. However, the gift turns out to be more of a curse when Merlin sees Morgana preparing to kill Uther and realises he faces the dangerous task of trying to change the course of destiny. Magical adventure series, starring Colin Morgan

 
Season 3 Episode 6
The Changeling Arthur is pressured to enter into an arranged marriage to Elena, a princess visiting from another kingdom. However, when Merlin learns the would-be bride has a dark secret, he sets about trying to discover what interest she could possibly have in pursuing a union with Camelot's heir. Fantasy drama, guest starring Miriam Margolyes, with Colin Morgan and Bradley James

 
Season 3 Episode 7
The Castle of Fyrien Gwen faces an impossible dilemma when she is forced to choose between saving the life of Arthur and her estranged brother Elyan, with one of them set to die at the hands of Cenred. She tries desperately to find a way out, but with Morgana and Morgause doing everything they can to thwart her efforts, the outcome looks bleak. Starring Angel Coulby and Emilia Fox

 
Season 3 Episode 8
The Eye of the Phoenix Arthur embarks on a quest to prove himself a worthy heir to the throne of Camelot by retrieving the Golden Trident from the Fisher King. However, Morgana spots an opportunity to attack the prince outside the safety of the citadel, and plays a trick that leaves him in mortal peril. Starring Colin Morgan, Bradley James and Katie McGrath, with Donald Sumpter (Being Human)

 
Season 3 Episode 9
Love in the Time of Dragons Gaius is overjoyed when an old flame arrives in Camelot, but Merlin discovers she has been possessed by an evil creature. However, the physician refuses to heed his young friend's warnings, putting the king's life in peril as a result. Guest starring Pauline Collins (Bleak House, Shirley Valentine)

 
Season 3 Episode 10
Queen of Hearts Morgana is tormented by dreams of Gwen becoming queen of Camelot and, encouraged by Morgause, reveals her and Arthur's courtship to Uther. When the king banishes the serving girl from the kingdom and his son resolves to follow her, Morgana frames Gwen for the crime of enchanting the prince - leaving Merlin no choice but to risk everything to save her from a gruesome death

 
Season 3 Episode 11
The Sorcerer's Shadow Camelot stages a legendary tournament attracting a great many warriors from far and wide, one of whom is small in stature but has a secret weapon - magic. As the young man begins to realise the full potential of his powers and resolves to use them to win the event, Merlin faces a race against time to make him see that his actions not only put his own life in danger, but also threaten to tear the city apart. Guest starring Harry Melling (Dudley Dursley in the Harry Potter films)

 
Season 3 Episode 12
The Coming of Arthur - Part One Part one of two. Arthur and Merlin embark on a dangerous mission to retrieve the cup of life, a powerful artefact that carries the gift of immortality. Before they can seize the magical goblet, they are captured by corrupt slave trader Jarl, who helps the cup to find its way into Morgause's hands. Fortunately for the duo, an old friend comes to the rescue, but with the power of eternal life at the disposal of Morgana and her sister, Uther's reign may be about to end. Guest starring Ralph Ineson (The Office)

 
Season 3 Episode 13
The Coming of Arthur - Part Two Part two of two. Newly crowned Queen Morgana begins her evil reign over the innocent citizens of Camelot while Uther can only stand by and watch as Morgause's immortal army causes the kingdom to crumble. On the outskirts of the city, Arthur regains his strength and decides to mount a counter-attack, but Merlin fears he will not be able to stop the deathless troops and tries to reclaim the great sword Excalibur to stop the destruction of all he holds dear. Last in the series

 
Season 4 Episode 1
The Darkest Hour - Part One Evil sorceress Morgana summons mighty gatekeeper the Cailleach, who opens a door to another world from which hellish creatures emerge. As Arthur and his loyal knights take up arms, Merlin discovers the only thing that will stop them is an unimaginable sacrifice. Colin Morgan returns as the young wizard in the first of a two-part story, guest starring Gemma Jones (the Harry Potter movies) and Emilia Fox (Silent Witness)

 
Season 4 Episode 2
The Darkest Hour - Part Two Part two of two. With the Kingdom on the brink of collapse and Morgana poised to strike, Arthur continues on his mission to the Isle of the Blessed. But with Lancelot racing back to the castle with the dying Merlin, there is no one to stop the prince making the ultimate sacrifice to save his precious Camelot. Sword-and-sorcery adventure, starring Colin Morgan and Bradley James

 
Season 4 Episode 3
The Wicked Day Camelot is buzzing in anticipation of Arthur's birthday celebrations, but the prince's old adversary Odin is determined this is a party the people will never forget, for among the carnival performers is an assassin ready to strike. When the hired killer makes his move, Merlin is left in an impossible dilemma - to put things right he would have to reveal the secret of his magic. Phil Davis (Whitechapel) guest stars in the fantasy drama, with Colin Morgan and Bradley James

 
Season 4 Episode 4
Aithusa A mysterious stranger arrives in Camelot claiming to have located the final part of a key to a tomb containing the last remaining dragon's egg. Merlin is intrigued and promises to help him - but the man's motives are soon called into question. Colin Morgan and James Callis (Battlestar Galactica) star

 
Season 4 Episode 5
His Father's Son Arthur faces his first true test as king when he incurs the wrath of the formidable Queen Annis - and as thousands of lives hang in the balance, he struggles to find the strength to become the leader his people so desperately need. Lindsay Duncan guest stars in the sword-and-sorcery drama, with Bradley James and Colin Morgan

 
Season 4 Episode 6
A Servant of Two Masters Morgana uses ancient magic to bend Merlin to her will, turning him into a deadly assassin on a mission to kill the king. But with Arthur oblivious to the danger, his only hope rests with someone else noticing his manservant's strange behaviour before he commits the evil deed. Colin Morgan, Bradley James and Katie McGrath star

 
Season 4 Episode 7
The Secret Sharer Morgana sets out to uncover Merlin's secret, an act that would change the course of destiny - and to ensure success, she joins forces with enigmatic wizard Alator, meaning the young warlock is more reliant on his friends and allies than ever before. Sword-and-sorcery drama, guest starring Gary Lewis (Billy Elliot), with Colin Morgan, Katie McGrath and Bradley James

 
Season 4 Episode 8
Lamia The young warlock is struck by a mysterious illness that draws him to a distant village where something sinister lurks. Before long, he finds himself embroiled in a deadly game of cat and mouse - but he cannot be sure if he is the hunter or the prey. Colin Morgan stars in the sword-and-sorcery adventure

 
Season 4 Episode 9
Lancelot du Lac Lancelot's return from the dead reignites old feelings for Gwen, forcing her into temptation - a contest that, if she loses, could lead her to commit an unspeakable act of betrayal that would destroy the legacy of Camelot for ever. But Merlin is suspicious about the knight's reappearance and believes something more sinister is at play. Magical adventure series, starring Colin Morgan, Santiago Cabrera, Angel Coulby and Bradley James

 
Season 4 Episode 10
A Herald of the New Age The knights discover an eerie shrine deep in the forest, which Merlin tells them is best left undisturbed. But the warlock's warnings go unheeded by Sir Elyan, whose careless actions spark a chain of events more terrifying than anyone could possibly have imagined. Sword-and-sorcery drama, starring Colin Morgan, Bradley James and Adetomiwa Edun

 
Season 4 Episode 11
The Hunter's Heart Morgana finds an ally in powerful warlord Helios and they plot to take over Camelot. However, Arthur and his people are so preoccupied with a visit from the beautiful Princess Mithian, it is left to the returning Gwen to raise the alarm - and her appearance soon reopens old wounds. Sword-and-sorcery drama, starring Colin Morgan, Bradley James, Katie McGrath and Angel Coulby, with Janet Montgomery and Terence Maynard

 
Season 4 Episode 12
The Sword in the Stone: Part One In the first of a two-part season finale, Morgana and her massive army close in around Camelot, and when she strikes, the ferocity of her attack forces everyone to run for their lives - even Arthur. But the sorceress will not let him escape that easily - and so begins a chilling hunt for the king. Can Merlin save his master's life yet again? Sword-and-sorcery adventure, starring Colin Morgan, Bradley James and Katie McGrath, with guest appearances by Ben Daniels and Miranda Raison

 
Season 4 Episode 13
The Sword in the Stone: Part Two Part two of two. Morgana and Helios have captured Camelot, leaving Arthur and Merlin on the run - and faced with the betrayal of a trusted courtier and the strength of the enemy, the king has lost the will to fight. It seems only the young servant can restore his master's faith - but only an extraordinary act can prove he was born to rule. Sword-and-sorcery adventure, starring Colin Morgan, Bradley James and Katie McGrath, with guest appearances by Ben Daniels, Miranda Raison and Terence Maynard

 
Season 5 Episode 1
Arthur's Bane: Part One Camelot faces a new golden age, but even as the city flowers, the dark seeds of destruction are being sown. In the frozen wastelands of the north, men are disappearing without a trace. King Arthur and his knights undertake a dangerous mission into the unknown in search of answers - but once there, Merlin finds himself locked in a battle unlike any he has fought before

 
Season 5 Episode 2
Arthur's Bane: Part Two Part two of two. Arthur and Merlin are exhausted as they make their way across the icy plains toward the fortress of Ismere, but with each tired step, the warlock's fear intensifies. What powerful secrets are Morgana and the druid Ruadan searching for among its twisted catacombs? And what dangerous game is Mordred playing? It seems not even Merlin can stop his king from walking into certain danger as the great battle for Albion begins

 
Season 5 Episode 3
The Death Song of Uther Pendragon A stranger gives Arthur the power to summon the dead, so he seizes the chance to speak to the person he misses most - his father, Uther Pendragon. But the young king's decision comes at a terrible price, for the spirit world is a dangerous place, leaving Merlin fighting against the odds to put right the mistake before Camelot is destroyed. Anthony Head guest stars, with Colin Morgan and Bradley James

 
Season 5 Episode 4
Another's Sorrow Morgana makes a sinister pact with Nemeth and King Odin, using Princess Mithian as bait to lure Arthur to his death - a deception so powerful that the whole of Camelot, even Merlin, is taken in. Can the young warlock see through the lies before it is too late? Fantasy adventure, starring Colin Morgan, Bradley James, Katie McGrath and Janet Montgomery

 
Season 5 Episode 5
The Disir In the inky depths of an ancient pool, a trio of soothsayers cast a dark judgement upon Arthur. But despite Merlin's warnings, the headstrong king refuses to take their words seriously, so their fury rains down on Camelot. With the kingdom in jeopardy, only the greatest sacrifice can appease them - but is it one Arthur is prepared to make? Colin Morgan, Bradley James star in the fantasy drama

 
Season 5 Episode 6
The Dark Tower Gwen becomes the traditional damsel in distress when she is snatched from Camelot and locked in a dark tower, so Arthur mounts his trusty steed and sets out to rescue his bride, accompanied by Merlin and his loyal knights. However, her kidnapper is none other than Morgana, who has imprisoned the queen in a place that haunts the dreams of men. Before them lays a landscape riddled with hidden dangers, perilous obstacles and magical beings - but surely, the sorceress wouldn't have made it quite that easy?

 
Season 5 Episode 7
A Lesson in Vengeance Morgana finds herself in a unique position of power, having a Camelot insider under her spell - and now the pair hatch a plot to murder the king. But when stable hand Tyr Seward becomes caught in the crossfire, he threatens to ruin everything. Can a suspicious Merlin unravel the truth before it is too late? Colin Morgan, Katie McGrath and Bradley James star

 
Season 5 Episode 8
The Hollow Queen The warlock agrees to help a young druid boy, Daegal, although to do so he has to leave Camelot on a dangerous mission - just as the citadel is playing host to the fearsome Sarrum of Amata. He hopes no one will notice his absence, but as the sky darkens so do Merlin's suspicions - is there more to Daegal than meets the eye? And can a man as ruthless as Sartre be trusted? Fantasy drama, starring Colin Morgan

 
Season 5 Episode 9
With All My Heart The warlock is determined to break Morgana's twisted control over Gwen. But it will be no easy task, even for Merlin, as only the most powerful magic can save the Queen - and the high priestess will not give up her puppet without a fight. Fantasy drama, starring Colin Morgan, Katie McGrath and Angel Coulby

 
Season 5 Episode 10
The Kindness of Strangers Morgana is desperate to find the warlock's alter-ego Emrys, and seeks help from an old foe, the powerful wizard Alator. Merlin's life has never been in more danger, so when the mysterious Finna offers to help him, is he right to trust her? Gary Lewis and Sorcha Cusack guest star, with Colin Morgan, Katie McGrath, Bradley James and Angel Coulby

 
Season 5 Episode 11
The Drawing of the Dark Mordred becomes torn between loyalty and love, little realising the path he chooses will shape Camelot's destiny - and as the drums of war beat louder, Merlin feels trapped by the cruel circle of fate. Can he really do nothing to stop his dreams of Albion crumbling to dust? Fantasy drama, starring Colin Morgan and Alexander Vlahos

 
Season 5 Episode 12
The Diamond of the Day - Part One In the penultimate episode of the magical adventure series, Morgana prepares to wage war on Camelot with Mordred at her side, while Merlin finds the burden of his destiny weighing heavily as the ancient prophecies play out with unnerving accuracy. It soon becomes clear that the young wizard must find a way to save himself before he can help his allies bring about the salvation of his beloved kingdom. Colin Morgan, Bradley James and Katie McGrath star

 
Season 5 Episode 13
The Diamond of the Day - Part Two As a fierce battle rages on Camlann's mighty plain, just as the prophecies foresaw, Merlin must find the strength to overcome his greatest challenge yet as he seeks a way to protect Camelot. As he fights to save the kingdom from the attacking hordes and keep Arthur safe from harm, the young wizard finally comes face to face with his destiny. The last-ever episode of the magical adventure, starring Colin Morgan, Bradley James and Katie McGrath. Last in the series