Call The Midwife star Oliver “Olly” Rix has said his new character on Casualty raises questions over “what it is to be a man” in the NHS.

The 40-year old will play Flynn Byron, a former special forces medic joining the fictional Holby City hospital team as a clinical lead consultant in the BBC series.

He will first be seen in the long-running medical drama’s 12-part miniseries called Internal Affairs, which airs on Saturday and will feature Cold Feet star Robert Bathurst who will play a top-tier surgeon.

Speaking about his character, Rix said: “I think he’s not a device. He’s not there to just sort of help tell a story. He’s a real human being. I think there have been some really interesting questions about what it is to be a man.

“I think those are enabled by having situated the character in a very specific, very niche, highest end, military kind of background initially, and then putting him into a different context has allowed us to ask a lot of different questions about what it is to be a father, what it is to be a husband, what it is to be a man in the work environment of the NHS.”

Flynn’s background in the special forces draws in new challenges, according to Rix, who describes the adjustment as “an amazing clash” as he is forced to learn how to operate in a bureaucratic institution like the NHS after being a “thinking soldier”.

On preparing for the role, Rix worked with former special forces operatives and received physical and weapons training – describing the work as “mind blowing”.

He said: “It was obviously a very interesting challenge, and something I’ve not done before.

“I think that they’re (the special forces) a very tight community, and it’s hard to get an in, but when you do, they were so generous with that information.

“It was mind blowing to think that you’d be watching a friend bleed out and trying to stem the blood flow, and at the same time you’re being shot at, you’re being thrown around in the back of a helicopter with night vision goggles on.

“It’s so claustrophobic and chaotic, and again, take somebody like that and put them into an NHS context. It’s going to be very different.

“Just a really great place to launch a character from.”

Rix is best known for playing Matthew Aylward in the BBC period drama Call The Midwife, as well as for his stage work with The Royal Shakespeare Company.

He has also been in the period dramas Death Comes To Pemberley, Spanish Princess and The Musketeers.

On Monday evening, the trailer for the new series of Casualty was released ahead of Rix’s debut on Saturday, which showed his character clashing with fellow NHS workers.

Casualty continues on Saturday on BBC iPlayer and BBC One.