Casualty spoilers follow.

Casualty is turning 40, and the BBC medical drama is celebrating the milestone in explosive style – quite literally. In a special double bill episode airing on Saturday (5 September), an explosion at St James’ Hospital leads to chaos in Holby ED, with a number of the much-loved team placed in grave danger.

Ahead of these milestone episodes, Digital Spy chatted to actors Olly Rix (Flynn), Elinor Lawless (Stevie), William Beck (Dylan), Neet Mohan (Rash) and Melanie Hill (Siobhan) about what we can expect from the anniversary

1. It’s Flynn’s birthdayflynn byron, casualty

BBC

In the opening moments of the big episodes, it is revealed that it’s Flynn’s birthday, and the clinical lead is in fact turning 40 alongside the show. His family celebrations are soon derailed, however, when he witnesses a huge explosion

“That really feeds into Flynn’s story,” says Olly. “I don’t think turning 40 is easy for him. He’s come from his military background, he’s slowing down and reassessing where he is in life, and having to face some pretty hard truths – his marriage has failed, he’s not with his daughters all the time, and he’s in a slightly vulnerable place.

“I think that’s important and deliberate, because he has to take and process the experience that he then lives through across the two episodes. This is a big moment for Flynn personally, as well as obviously massive for the show.”

2. Holby is under pressurematty linklaker, casualty

BBC

“The episode starts off with a massive explosion,” says Melanie, previewing the action in the ED, “but then there’s an ongoing threat of a continued terrorist attack. The stress levels are high, and the team don’t know what’s coming through the door.

“That’s the same for every day in an A&E department, but this particular day, they’re not only treating the patients who have been injured in the explosion, but also those who were being treated at St James’ and are brought over.

“The team are making very hard decisions before the patients even get into the hospital, as they have to triage everyone outside.”

3. The whole cast is involvedcam, dylan, rash, masum, rida, stevie, casualty

BBC

While there are usually several strands to each Casualty episode, the anniversary episodes see the entire team puts their personal problems aside and come together to save as many patients as possible.

“It was great fun and it felt like a real privilege to be filming these episodes with everyone,” Neet remarks. “They’re such ambitious episodes. And everybody pulling together the way they did make it really special to film.”

“When productions like this are announced, it’s like sports day and the school production, and the level of excitement is exactly how you would feel for that,” adds Will. “There’s loads of responsibility and the material is invariably that bit more heightened, but it’s just thrilling.”

4. Rash is forced to step uprash masum, casualty

BBC

At the end of the last boxset, viewers celebrated Rash successfully qualifying as a consultant. But his very first shift in his new role happens to be the night of the explosion, and he is pushed far out of his comfort zone.

“Rash has always struggled with his confidence, and I think he’s doubted himself a lot in the show,” Neet reflects. “He cares so much about his patients and the people around him that I think it can be a blessing and a curse. But in this moment, he’s got to trust all of his experience and trust himself a bit more to try and overcome this.”

5. Dylan faces tragedydylan keogh, casualty

BBC

With Flynn away from the hospital, Dylan is looked upon to take charge and tell everyone what to do – but he begins to find it challenging when he faces his own personal tragedy during the incident.

“When the explosion goes off, visually the consequences begin,” explains Will, “but for Dylan they go off a little later internally. I think Dylan offers an early example of how great an impact something unexpected is going to have on so many different people.”

6. Stevie and Flynn are in dangerstevie nash, casualty

BBC

Meanwhile, Flynn and Stevie are on the scene treating victims of the blast. But things go seriously wrong, and the pair find themselves trapped underwater in an ambulance!

On filming these dramatic scenes, Elinor says: “Stevie’s nemesis in this episode is water – and water does not care about you! Filming those sequences was really scary, but the team were so professional, kind and gentle. It was useful because you didn’t have to go too far into your imagination to capture just how Stevie would be feeling.”

“Flynn and Stevie are thrust into a situation that is totally out of their control,” Olly adds, “and the odds are massively stacked against them. There’s a point where one of them might not make it.”

7. There are big guest starsdr alex kavanagh, casualty

BBC

A big event calls for a big cast, and our core cast members were full of praise for the guest stars, including Pippa Hayward (Dr Alex Kavanagh), Kent Riley (PC Jim Harkner) and Clare Perkins (Cheryl Pritchard). Plus, who knows who else might walk through the ED doors?

“50% of our cast each week is a guest cast,” points out Will. “Essentially, it’s a bit like institutions such as the NHS – it retains the experience of those people who’ve worked on it. I hope we continue to exhibit the very best of what goes on in the industry.”

8. Expect the unexpectedfaith dean, siobhan mckenzie, casualty

BBC

“There are a lot of twists and turns,” says Melanie on the all-important anniversary episodes. “It leads you down a path, and then suddenly it takes you in another direction.

“I think that’s quite exciting, and it’s nice having the two hours because it’s got plenty opportunity to surprise you. There were a few bits where I was like, ‘No way!’ – and I’d read it!”

9. There are glimmers of hopeindie jankowski, casualty

BBC

While this is one of the darkest instalments in recent memory in Casualty, with some heartbreaking and distressing moments, the cast insist that there is still a sense of optimism running through the episodes.

“Hope is the word,” Melanie reflects. “I think it’s really important because you don’t realise how strong you are as a person until you face these massive tragedies. People might face things that have happened in this episode in a smaller way. I think that’s what Casualty does well – it manages to touch people in their lives.”

10. A new era is approachingmatty, nicole, rida, casualty

BBC

The anniversary episodes honour the last four decades of Holby for avid viewers, but they can also serve as a introduction to the show for new audiences, or a reintroduction for those who haven’t watched in years. After all, there are some big changes ahead…

“This is a new show with a different intention,” Olly teases. “We are entering a new era. I think the 40th is the perfect springboard into that and this will continue beyond the anniversary.”

To read our full exclusive chats with the cast, pick up the latest issue of Inside Soap, available to buy from Tuesday 1 September – which contains a whopping 23 pages of Casualty content!

Casualty‘s 40th anniversary double-bill airs on Saturday 5 September on BBC One and BBC iPlayer.

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