Casualty cast 2026: Episode 1 tonight includes brutally banished Traitors star's return and two new regulars as resident doctors
Meet Kim and Matty – and a familiar Faithful!Casualty is back tonight for 2026 after a long break, with two new regular cast members joining the BBC One medical drama and a very familiar face from The Traitors playing a guest character in episode one.
There’s a whiff of new beginnings in the latest series, titled Learning Curve, with Flynn and Stevie becoming mentors to two fresh resident doctors, Kim and Matty, as they begin rotation in the ED – and Dylan may or may not be the father of the latter…
Plus, a rather legendary Faithful from The Traitors, who suffered a torrid time on the show, makes a Casualty comeback, in an equally painful-looking TV appearance.
Here’s everything you need to know as Casualty returns for its 40th year!
*** Warning – contains some spoilers ***
When is Casualty back on?
BBC One airs the first of 12-part series Learning Curve on Saturday, January 10, 2026, and will air subsequent episodes weekly on the same day.
Casualty’s exact air time can change throughout its series, so we’ll keep you posted each week – or you could check our dedicated Casualty schedule page in the TVGuide listings.
Tonight’s episode one airs from 8.45pm, and is 50 minutes long. The BBC is dropping an episode each Saturday at 6am on iPlayer if you like to watch it early, and they will all remain available at least throughout the series.
What happens in Casualty 2026 episode one?
As befits the series name Learning Curve, there are new beginnings for the staff of the emergency department. Most significant is the arrival of two new resident doctors, Matty (Aron Julius) and Kim (Jasmine Bayes).
The pair are assigned, respectively to Flynn – after Dylan refuses to be a mentor – and Stevie. While Matty immediately impresses Flynn with his clinical skills, Kim feels the wrath of Stevie when she hits the emergency alarm not once but twice, unnecessarily as it turns out.
But one should not always trust first impressions!
Meanwhile, Dylan is left questioning if he might have a huge connection to newcomer Matty, when he discovers he is the son of his old flame Sarah and his age – 25 – stacks up to around when they were together. Is Dylan Matty’s dad?
Elsewhere, it’s clear relations between Iain and Faith are not good after he told her in the Casualty 2025 finale that he didn’t love her, he just had a need to try and save her. Still ouch!
As for patients, on the hottest day of the year a chippy young woman – played by that star of The Traitors (keep reading!) – appears in the ED with dreadful sunburn and a heartbreaking back story.
Casualty cast 2026 joined by two new regulars playing resident doctors
Dr Matty Linlaker in Casualty – played by Aron Julius
Matty jogs to his first day at work in the ED without even breaking sweat, setting up his character immediately as cool, calm and collected – and very confident. Or so it seems. As the day progresses, it’s clear Matty is a competent medic, but he’s not prepared for what life is like for doctors in the cash-strapped, resource-poor NHS.
Also, unbeknown to Matty, Dylan realises that he knew the young doctor’s mother back in their uni days – as in, really knew her. And Stevie plants the seed that perhaps Dylan is Matty’s dad.
Matty actor Aron Julius doesn’t have lots of screen credits to his name yet. However, Aron had a role in Silent Witness last year. In 2022, he had a part in Death in Paradise, and in 2015 he featured in ITV cop drama DCI Banks.
The RADA-trained actor also has a string of respected theatre credits to his name, including multiple Shakespeare productions.
Aron Julius says of his high-profile new TV role: “I am absolutely buzzing to be joining Casualty as Dr Matty Linlaker. It’s a dream job – fast, fun and full of heart – and I can’t wait for audiences to meet him. Saturday nights just got a little more chaotic.”
You can follow Aron on Instagram, where his handle is thescousethespian.
Kim Chang in Casualty – played by Jasmine Bayes
While Matty appears ED-ready, Kim looks set to be eaten alive, with her fluffy pink pen, hair in bunches and home bakes for her new colleagues. And Stevie wastes no time in concluding Kim is not ED material – despite proving her medical knowledge is exemplary. But, about those first impressions… it’s clear there’s more to Kim than meets the eye.
Actress Jasmine has had roles in some seriously high-profile shows in the past few years, from Doctor Who and Vera to Father Brown and ITVX sleeper hit Platform 7. This year, as well as Casualty, she appears in season 2 of Apple TV +’s Hijack.
Jasmine Bayes says of her role as Kim in the BBC medical drama: “I am delighted to be joining the ED alongside Aron for Casualty’s 40th year. The journey Kim goes on is far from simple, and I hope audiences are prepared to follow her into some troubled waters.”
Casualty guest cast tonight (January 10, 2026) – The Traitors series one actress Madelyn Smedley
If the patient with very painful-looking sunburn looks a little familiar to you, it could be because you recognise her from roles in Call the Midwife, Hollyoaks or EastEnders – or from her much more memorable stint on The Traitors.
Madelyn Smedley, aka Maddy, who plays Bethany in Casualty tonight, appeared in series one of The Traitors in 2022. She has worked on TV as an actress both before and after her stint on the hit BBC entertainment show. She’s actually appeared in Casualty before, too, as a woman with no womb.
Maddy joked of her return to Casualty on social media late last year: “Every 18 months you can play a new injured person on Casualty. This time I’m playing a woman who had melanoma. So on 10 January I’m back on @BBCCasualty! See you then at 8.45pm.
“LOVE working on the show, always the best creative team – and cheers for keeping me employed!”
What happened with Maddy Smedley on The Traitors?
Maddy was a Faithful in the first ever series of The Traitors and rightly guessed from early doors that Wilf was a traitor. The Faithfuls only exposed him in the final episode of the series, after they brutally banished poor Maddy.
The other players became suspicious of her focus on Wilf. Her decision to keep quiet about being an actress for most of the series didn’t help. At a particularly excruciating point they voted her the least trust-worthy of the pack. Her fellow contestants even offered her a £3,000 bribe to leave the game.
She refused it, but the others still didn’t trust her! In the penultimate episode, the players banished her. And the next episode they discovered her hunch about Wilf had been correct!
