As Casualty prepares to celebrate four decades on screen, one of its longest-serving stars has offered the first tantalising hints about what viewers can expect from the landmark 40th anniversary episode — and it sounds set to be something truly special.

William Beck, who plays clinical lead Dr Dylan Keogh, has described the upcoming instalment as “beautiful”, promising that it will showcase the drama in a way fans may not have seen before. With the BBC medical series first launching in 1986, the anniversary marks an extraordinary achievement for a show that has become a Saturday night institution.

While producers are keeping major plot details under wraps, Beck has suggested that the episode will step slightly outside the show’s usual format. Rather than focusing purely on high-intensity trauma and emergency department chaos, the anniversary is expected to lean into character, legacy and reflection — themes that feel fitting for a series built on decades of life-and-death storytelling.

“It’s a beautiful example of the show coming out of where it normally sits,” Beck teased, hinting that the milestone won’t just be about spectacle, but about heart.

For longtime viewers, Casualty has always balanced adrenaline-fuelled medical emergencies with deeply personal character journeys. Over the years, audiences have watched Dylan battle obsessive-compulsive disorder, struggle with alcoholism, and now confront one of the biggest revelations of his life — discovering that trainee doctor Matty Linklater is his biological son. That kind of emotional depth is part of what has allowed the show to endure.

The anniversary episode is widely expected to honour that legacy.

There is speculation that past characters could be referenced, and that the episode may reflect on how the emergency department — and the NHS itself — has evolved since the series first aired. From grainy 1980s corridors to modern, high-tech trauma bays, Casualty has chronicled not just fictional lives, but the changing face of frontline medicine.

For Beck, who has been part of the show on and off for nearly 14 years, the milestone carries personal significance. Few actors get to be part of a drama that spans generations, and fewer still remain central to its storytelling during such a landmark year.

The timing of the anniversary also coincides with some of the show’s most emotionally charged current storylines, including Dylan’s secret about Matty and Kim Chang’s ongoing struggles under pressure. If the special episode truly “comes out of where it normally sits”, it could provide a powerful lens through which to examine not just the hospital’s history, but the characters’ futures.

What makes this celebration especially meaningful is that Casualty has never relied solely on nostalgia. Instead, it continues to evolve — introducing new faces, tackling contemporary issues, and pushing its characters into uncomfortable, complex territory.

Forty years on, the series remains rooted in the same core idea: that behind every medical emergency is a human story.

If Beck’s early description is anything to go by, the anniversary episode won’t just mark a date in television history — it will remind viewers why they’ve stayed with Holby for so long. And in a show built on survival, resilience and second chances, that feels like exactly the right way to celebrate.