Blue Lights series 4 on BBC One: Writers have 'brilliant ideas' about 'where to take the characters next'
Helen Fear | 12:17pm Mon 29 SepBlue Lights fans – whether you’ve already devoured series 3 on BBC iPlayer or are waiting patiently for the weekly Monday 9pm slot – will be thrilled to learn that a series 4 has been confirmed.
The brilliant police drama, set in politically turbulent Belfast, returned with new episodes at the end of September 2025.
And we can expect more of the same in 2026. Here’s everything we know so far about Blue Lights series 4 on BBC One. We’ve been careful not to include any spoilers for series 3.
The cast of Blue Lights will be back for a series 4 in 2026 [Credit: BBC/Two Cities Television/Matthias Clamer]
Is there a series 4 of Blue Lights?
Blue Lights series 3 is every bit as good as the previous two series… So viewers will be pleased to know there’s at least another series incoming.
BBC One has confirmed that a series 4 of the hit Belfast police drama has been commissioned. And we don’t see any reason at all why the drama can’t run and run for years. It has already escaped the dreaded series 2 curse, where the second run failed to live up to the first. See The Last of Us, Squid Game, and Nine Perfect Strangers for examples.
If co-creators and writers Declan Lawn and Adam Patterson carry on writing as well as this, we could watch until the end of time.
Unsurprisingly, series 1 became one of the top 10 new drama series of 2023 across all broadcasters and streamers, and the biggest drama series in Northern Ireland.
‘A gripping drama about ordinary people doing an extraordinary job’
The BBC has ordered at least one more six-part series of the critically acclaimed Belfast-based police drama Blue Lights.
They described the drama as “an authentic, gripping and darkly funny drama about ordinary people doing an extraordinary job”.
Series 1, which aired in 2023 to critical acclaim, introduced three new PSNI probationary recruits Annie, Tommy, and Grace. Together with more experienced frontline response cops, they worked one of the hardest beats in the UK – Belfast, a city with unique pressures and dangers.
Series 2, which aired in 2024, reintroduced the three rookie coppers a year into the job. This time, the team were faced with a drug-fuelled crime wave that led them into a loyalist estate.
The current 2025 series 3 meets the Belfast police response officers two years into their jobs. While Grace, Annie and Tommy are accustomed to life under the blue lights, their work continues to be challenging – and dangerous.
The synopsis tells us: “Their work takes them into a sinister world hidden behind the veneer of middle-class life, the world of the accountants and lawyers who facilitate organised crime.
“The old political and criminal order has gone and a new global gang rule Belfast, bringing danger closer to home for our officers than ever before.”
How many episodes is Blue Lights series 4?
The next series of Blue Lights will be six episodes of an hour long.
This follows the exact format of the previous three seasons.
How can I watch Blue Lights?
Blue Lights series 1 to 3 are currently all available to watch on BBC iPlayer.
That’s 18 hours of gripping police drama right there.
Who will return in the cast?
Although not yet confirmed, we’d expect to see the follow fan-favourites reprising their roles in the forthcoming series 4 of Blue Lights:
Siân Brooke as Grace Ellis
Martin McCann as Stevie Neil
Katherine Devlin as Annie Conlon
Nathan Braniff as Tommy Foster
Joanne Crawford as Helen McNally
Andi Osho as Sandra Cliff
Frank Blake as Shane Bradley
Dearbháile McKinney as Aisling
What’s the plot of Blue Lights series 4?
It’s early days to know much about the plot, but the Beeb has teased some “brilliant ideas”.
BBC Director of Drama Lindsay Salt said: “We were bowled over by the reaction to Blue Lights and I’m really pleased to be confirming our commitment to bring more series of our beloved Belfast drama to air.
“Adam and Declan have brilliant ideas about where to take the characters next and I can’t wait for viewers to see what’s in store.”
In a statement about Blue Lights series 4, co-creators Declan Lawn and Adam Patterson said: “We’re thrilled that the BBC is committing to Blue Lights in this way. From the beginning, we wanted to write a show that had scale and ambition in its storytelling. And this decision gives us everything we need to do that. Thanks to our brilliant cast and crew. But most of all thanks to our audience who have responded so powerfully to the show. Time for us to get to work!”
More details including the cast and plot for series 4 of Blue Lights will be announced in due course.
