This article first appeared in Radio Times magazine.
On a cold and wet January morning, Radio Times are ushered into the hallowed corridors of Pinewood Studios in Buckinghamshire. At the time, production has just wrapped on an impressive scale-replica of the New York backstreets, which can be seen in the latest Tom Holland vehicle, Spider-Man: Brand New Day.
But on the other side of the studios’ sprawling 200+ acre backlot, the cast and crew of Casualty are calling the historic site their home for the week.
It’s a stark difference from their usual confines at BBC Roath Lock in Cardiff. Although the set-up of the fictional Holby City Hospital is impeccable, it doesn’t boast a 20ft deep underwater stage.
Actors Olly Rix and Elinor Lawless needn’t worry about the drizzly weather conditions, as they’re about to take a plunge into the tank for one of the medical drama’s most ambitious stunts.

The stunt was filmed at Pinewood Studios. Michael Adams for Radio Times
It’s all in aid of the series’ 40th anniversary, which will see their alter-egos Flynn Byron and Stevie Nash facing a life-or-death situation beneath the murky waters of a flooded quarry.
How our heroes find themselves in this predicament will be explored during a double-bill of episodes on Saturday evening.
“I just love that sense of the industry that’s gone ahead of you; I’ve seen the dinosaurs from Jurassic Park, the Bond stages. I guess that’s a statement about what the show is intending to do,” Rix tells me.
“There’s been a conscious effort to level up with the storytelling and the production value in these instalments.”
Both stars have undertaken days of diving training before the dip. These environs are just as alien for the crew as they are the performers, and so there’s stunt performers on hand for the unit to ‘block’ a more complex take.
“It’s obviously such a foreign thing to be doing, taking direction and having an actual clear narrative underwater,” Rix adds. “That’s a whole extra layer of complexity.”

RT soaps editor Michael Adams (centre) with stars Olly Rix and Elinor Lawless at Pinewood Studios. Rob Parfitt for Radio Times
In a make-up trailer outside, Lawless laughs when telling me she suffered a “mini breakdown” during rehearsals.
“I was worried about letting everyone down,” she admits, “but the team here are amazing, and I can’t believe that I now feel so relaxed in this environment.
“I don’t have to dig too deep to find something authentic in terms of Stevie’s fear.”
One small mercy is the fact the water is permanently heated to a toasty 32 degrees, with the lights of an ambulance illuminating the steam that radiates from the surface.

Lawless told RT of her “mini breakdown” during diving training. Rob Parfitt for Radio Times
With a smirk on her face, Lawless remarks: “You really feel the cold when you step out, so I do enjoy getting back into the ‘spa’!”
Casualty was conceived as an exploration of the NHS during Thatcher’s Britain, though the strain that our medical frontline faces is now far greater than it was four decades ago.
With record-high waiting lists, severe limitations on social care and an aging population, the scripts effectively write themselves.

Rix believes the drama continues to parallel the real-life NHS. Rob Parfitt for Radio Times
“There are certainly elements of the show that are very reflective of the inevitable fall towards privatisation, and the sense of being consumed by the place you work at,” comments Rix.
“When it comes to Flynn specifically, he always has an issue with the bureaucracy and the red tape that he feels gets in the way of patient care.
“I’m by no means an expert, but from conversations I’ve had, it certainly seems to be a consideration that a lot of doctors face.”

The drama usually films at BBC Roath Lock in Cardiff. Michael Adams for Radio Times
When I join the team on their return to Roath Lock, I realise just how indebted they are to the advisors who ensure accuracy and clarity of the terminology and procedures we see on screen.
Script editor Daisy Hayes recalls that, due to what has been achieved with the anniversary, medics were on hand from the outset.
“We had doctors who have been involved in mass casualty events giving us ideas of what would happen in a city of Holby’s scale. They also accounted for the fact people would get involved in the tragedy before professionals arrived at the site,” she explains.
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“They consulted on the different kinds of injuries you’d see, and most of them were inspired by stories that patients had told us.”
The person responsible for executing these special effects is series make-up designer Kirstie Stanway, who has been with Casualty across multiple stints for the last 25 years.
Her office is littered with open wounds, severed body parts, and a 3D printed chest cavity that was recently used to portray heart surgery.

Kirstie Stanway and her team work on the make-up and prosthetics. Michael Adams for Radio Times
“We had a really wonderful guy who was an amputee allow us to make a fake leg for him and then build up one of his residual limbs as if he’d been in a blast,” Stanway tells me.
“We did a trial fitting with the actors before they came in, and then I sent the photos off to the medical advisors to make sure they’re happy with it.
“I sit in a lot of meetings with those guys to thrash out things together and often turn up with what I call my ‘book of horrors’ – it’s images I’ve pulled off the internet that can make everyone feel a little bit sick but are crucial to the process.”

“I’m glad Siobhan isn’t a paramedic because those handovers are just awesome.” Radio Times
Melanie Hill, who has played Siobhan Mckenzie for the last two years, is thankful that nobody has ever asked her to sew up their wounds.
“I’m sure I could do it. Actually, no, I really couldn’t,” she laughs.
“We do get a glossary of jargon, though I’m glad Siobhan isn’t a paramedic because those handovers are just awesome. They’re saying so many things at once.”
Despite the inevitable losses that are part and parcel of the drama, there’s also a celebratory tone to these episodes, with the overriding message being that ‘Life Begins at 40’.

The show will be leaving the environs of Holby City Hospital next year. Rob Parfitt for Radio Times
It’s an evident nod to the great change ahead for those on the Cardiff backlot – a new chapter in history of the world’s longest-running primetime medical series is about to be written, with the set of the infamous emergency department being dismantled later this year.
A new Welsh infirmary is waiting in the sidelines to be built. The BBC are keeping tight-lipped over how these changes will be addressed next year, but it all forms part of the institution’s desire to ‘include authentic representation of Wales and reflect the reality of the Welsh NHS.’
Fear not, there won’t be a mass exodus of our favourite medics. I’ve been assured that a sense of familiarity will be retained, and there’s every possibility that the Clifton Suspension Bridge will allow for an easy commute, just as it did for legendary nurse practitioner Charlie Fairhead in the very first episode.

The episode pays tribute to the very first episode. BBC
In fact, Casualty pays homage to Charlie and his little yellow VW Beetle in the opening scenes of the 40th, as a similar vehicle rolls past Flynn when he witnesses an explosion engulfing the skies across the fictional Wyvern Valley.
“This is simultaneously a nod to the past – with a lot of warmth and gratitude – but also a statement that Casualty is in a different era,” Rix adds.
“It’s the show as you remember it, but in a new phase of evolution. It’s changing and getting broader and bigger. The production value is increasing.
“We’re modernising rapidly, and that’s just as exciting for us actors as it is for the fans.”
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Casualty returns on Saturday 5 September on BBC One at 8pm.
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