A NEW year brings new faces to the wards of Holby City as cardio thoracic registrars Joseph Byrne (played by Luke Roberts) and Sam Strachan (Tom Chambers) join the team.

''It's been terrific,'' smiles 28-year-old Luke when asked how he's settling into the job. ''Holby has a very nice cast who are extremely welcoming. I was fortunate to come in with Tom and Rosie Marcel (who we first saw on our screens in November as Jac Naylor), so there is a feeling of solidarity between the three of us.''

Nevertheless, he admits he was a tad nervous about his first day in the role. ''It was a filmed rehearsal in front of all the producers of a script I'd only recently received. We were constantly reassured it wasn't a test, but of course you can't ever get it out of your mind. Tom and I were bricking ourselves, but it was a good first hurdle.''

As if that wasn't challenging enough, Luke also had the problem of getting his tongue round some seriously complicated medical jargon.

''The trick is to say it with confidence and people will buy it,'' he laughs. ''At the beginning I tended to look up all the diagnoses I was giving, but after a while you realise you'd need years and years of training to fully comprehend exactly what you were saying. But we get the general gist of it because we have on set advisors all the time.

''Joseph's very stuck in his ways,'' he adds, ''in so far as he's rather bookish, very strait-laced and incredibly meticulous to the point that it develops into a disorder. I'm not sure how much I can say about that, but it's going to evolve and it's really fun to play.

''When I got the part I thought, 'Here's someone with scope'. His problem does manifest itself in some pretty interesting ways. Of course, it allows for a little bit of comedy as well, because he clashes with his counterpart Sam, who is quite the opposite of Joseph.

''It's almost as if Joe's been brought up in a hermetically sealed box surrounded by books and has only recently been unleashed on the world.''

Despite the character's flaws, there are elements about him Luke likes.

''He's a perfectionist. I would love to claim I'm the same, but having said that, he does take it to ridiculous lengths.

''I certainly admire and envy his punctuality. I couldn't be accused of having that trait, I'm afraid. I think he's very honest as well. There's not a lot of deceit there and he's very guileless. As a result, even though he would like to excel he's not necessarily the best political animal in the world.''

Although January marks Joseph's debut, it's not Luke's first brush with Holby. ''In May last year, I played the son of a surgeon who died after being mysteriously over-anaesthetised on the table. Understandably, he was a very angry character. It was only one scene really, but I think it was enough to get me called in for this part.

''Certainly when I was doing it I did kind of hope it would lead on to something more, because the place had a really nice atmosphere. I was working with Art Malik and Amanda Mealing and they were very welcoming.

''Now I'm in the show full-time, I don't really know what impact it's going to have on my life. It certainly keeps me in work, which is a real bonus for any actor, and it's close to where I live, which is terrific. I guess there will be some loss of privacy too, but I can't imagine it's anything like the scale of being in something like EastEnders.''

Luke's first gig out of drama school was certainly an impressive one.

''I was in Band Of Brothers,'' he says. ''That was more like working in the film world, really, with the time they took over everything and the budget they had to spend.

''It was my first job and my first audition. I went on set shaking hands with Tom Hanks, who was directing it, which was pretty exciting. It was an interesting experience. I was playing a raw recruit being sent to the front lines, and that's pretty much how I felt.

''Before I started, I remember worrying, 'Gosh, I hope I don't get star struck', but actually I wasn't and it was just a very nice time. Tom was a pretty cool guy and put everybody at ease.

''I remember thinking, 'Right, I'm an actor now', but it was followed by six months of unemployment. However it was a great job to start with because it did lead to a lot of auditions.''

A role in the ill-fated Crossroads revival proved to be equally memorable, albeit for different reasons.

''I was in it for six months and I loved doing it. It was my first regular gig. I was in the final incarnation of the show with Jane Asher, playing her wayward playboy son. The show was high camp, and for me that meant a lot of gambling and Jacuzzis. But those Jacuzzis were freezing cold and the scenes tended to be first thing on a Monday morning, when you were hardly in the mood. But I had a great character and got to work with some really nice people.

''It was a baptism of fire. I learned a lot really quickly, including the fact you can never really count on anything, because all of a sudden it was axed.''

As for his future, Luke's got a clear vision. ''Movies - that's what I want to go for,'' he says. ''I love television because it's so fluid and constantly evolving, but I grew up on films. I always wanted to be an actor through school and university because of movies.''

* Holby City is on BBC One on Tuesdays at 8pm. Tonight, cardio thoracic registrar Joseph Byrne joins the team.

Mike Amos is away