Call the Midwife's Olly Rix explains what convinced him to join Casualty

We last saw Rix on our TV screens when his character Matthew Aylward left Poplar and headed to New York amid a flurry of financial difficulties, and while Call the Midwife is a medical drama too, Rix will be much more hands-on in this role.

With this being quite the jump between characters, Rix spoke exclusively with RadioTimes.com about his decision to join Casualty.

"I had lunch with the executive producer and we talked about the character in a lot of detail," he explained.

"We spoke for about three hours and I just thought she was wonderful, and I really liked her vision for the role, for the role within the series.

"The way the series was going, it was just modern, relevant, exciting, and just something I really wanted to be involved in."

Rix's character, Flynn, has been described as "a man with a purpose and with a fierce resolve to make a difference", as he joins the NHS fresh from a tour of duty, something Rix researched heavily ahead of filming for the series.

He told RadioTimes.com: "I managed to do some some fascinating research with some special forces soldiers and they were extremely generous with their time and the level of information that they imparted to me, not specifically about military stuff, but I asked them very blunt questions about what their relationship was like to death, mortality, how that made them feel about their families, what it was like when they would go away on tour.

"And of course, when you first meet Flynn, he's only a few days away from going on tour himself. I really tried to honour what they told me and what they very generously shared with me, and sort of put that into the character."

When viewers first meet Flynn, "he is very tightly wound and he really is a sort of coiled spring", but as the series continues, Rix believes viewers will get a closer look at Flynn's relationship "with past demons or mistakes and whether or not he wants to to recognise his blind spots and make a change".

Rix continued: "So it's quite a journey, really, from the initial episodes. We were very deliberate about making [him] heavy, like his weight heavy, to give him a different sort of inner tempo and a different physicality to other people in the world that he's about to come into.

"The world he's about to come into is a civilian world, and really, initially not his world. And then over the course of the series, you see that shed a bit. You see him soft, and you see his sense of humour, his playfulness, and he's flawed, so sort of watching him navigate all these things at once."

Casualty continues at 9:20pm on Saturday 15th February on BBC One. The episode will be available from 6am on BBC iPlayer. Previous episodes are available to stream on iPlayer now.

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