Actor Jonas Armstrong has appeared in TV programmes including Teachers and Ghost Squad but now he's got his largest role yet, starring as Robin Hood in the BBC's new big-budget version of the bow-slinging saga. Armstrong makes his much-hyped debut in the first show, which can be seen tomorrow at 7pm on BBC1.

Robin Hood is in the Dr Who slot. Do you feel under pressure to live up to that show’s success?
Dr Who has rejuvenated that slot. It’s done very well, so there is a pressure to emulate that success. You’ve just got to look at it positively.

Why did you get the part?
I’m always polite in auditions but I wasn’t like Oh, please give me the job’ for Robin Hood because I didn’t think I’d get it. I got told about the audition just a few days before I went to India to film something else. I must have been a bit cocky with it. I went into the casting room and perched myself on the desk rather than standing there nodding. I didn’t think I had a chance in hell but there you go.

Why did you go into acting?
I was always doing impressions of teachers at school. I was never one to knuckle down -I was always the one who was more interested in being the dickhead at the back of the room. I was always interested in films and thought that was the path I should go down but I didn’t start pursuing acting until I was 17. All my friends were choosing university courses but I had no interest in anything other than acting, so I applied to go to Rada. It’s got a reputation for having a certain type of posh students but that image was smashed when I got there -everyone was from different backgrounds and I made some really close friends.

What training did you get for playing Robin Hood?
I got there a week before filming started and, as soon as I arrived, I was out on the horses, then doing unarmed combat, archery and sword fighting every day. It was an ongoing process. We practised every minute we got because we’re all supposed to look very capable with the weapons.

How good are you at shooting arrows?
Pretty damn good now. I’ve been doing it for quite a bit. I’m all right.

The Hungarian stuntmen are as hard as nails and want you to actually hit them so they can react properly

Can you shoot an apple off someone’s head?
No, but I can hit a tree from a bit of a distance -that’s about it.

How good are you now at beating up people?
Much better. The Hungarian stuntmen are as hard as nails and want you to hit them. They’ve got the padding on but they want you to actually hit them so they can react properly. Sometimes you’re worried they’ll smack you back but they never do.

When was the last time you had real-life fisticuffs?
In my early 20s, about five years ago.

Who came off best?
I can’t remember [laughs].

But I guess you’re pretty confident now?
I’m not going to start shouting my mouth off, inviting people to ‘Come and have a go’. No. I’m not answering these questions any more [laughs].

Robin Hood robs from the rich. What have you nicked?
I’m a clean liver, I’m no thief. Kids go through phases of nicking stuff. I’ve nicked stuff -most people have but I haven’t nicked anything of significance.

Colonel Tim Collins, the former Army commander, visited the set. What tips did he give you?
He came over because some of the producers were concerned about how they wanted us to behave with our body language, and so on. Robin Hood is often seen as the hands-on-hips, archetypal, tally-ho hero. But, realistically, the one calling the shots wouldn’t be at the front shouting about it. He’d be the one you don’t expect. Tim told us about that and I wanted Robin to be a more believable understated leader because you’d have to be. And he told us all about killing people [laughs].

Did you really see a ghost while making the series?
Sort of. We were in a forest on a night shoot. It used to be used by thieves to stash their goods -which we didn’t know about. It was dark and the lighting guy took a picture. In the picture, about four trees behind us, there was some kind of shape with quite a distinct face and musket helmet. That freaked out me and the producer because we were the only ones there. But when the others saw the picture, they said it was the lighting. It didn’t look like lighting to us.

There was a story the film tapes were stolen by Hungarian thieves. Was it true or a publicity stunt?
It really did happen because we started reshooting some of the scenes. It’s hard to go back and try to do stuff if you think you’ve done it well the first time -but thank God it got sorted out. The people got caught and the tapes were recovered.

This is the highest profile thing you’ve done. Are you ready to become a sex symbol like previous Robin Hoods?
I’m a 25-year-old single guy -I’m not going to complain if that happens. I’m not saying it’s going to happen but if it does, I don’t think that’s going to be a bad thing [laughs].

What else have you got lined up?
The last play I did was nearly two years ago, so it would be good to get on stage -either that or get a part in a British film.