Sir Derek Jacobi discusses why he is involved with Vicious...

What attracted you to this project?

I saw it was very, very funny. I heard that they had asked Ian to be in it as well. Ian and I have known each other for over 50 years, but we have rarely worked together as our careers have taken different paths. So the prospect of doing this very funny sitcom with Ian sounded too good to miss.

Please talk us through your character...

Stuart is the sweeter of the two, but he can give as good as he gets when he's up against it. Whereas Freddie has had a career, Stuart hasn't. He's never found something he is passionately interested in. He's done jobs - he's worked in retail and waited tables. But he and Freddie met in their early 20s, and Stuart was in awe of Freddie's career as an actor to begin with. So he has just devoted his life to him, looked after the house and finances and made sure Freddie's ego was always boosted - which has been absolutely a full-time job!

Can you articulate the other differences between Stuart and Freddie?

Stuart doesn't have such a big ego. He doesn't need to be bowed down to all the time. Freddie needs a lot of praise. Stuart doesn't, but he is still rather sad that he has never found a proper niche. Instead, he has dedicated everything to Freddie. Particularly when Freddie is so rude him, Stuart thinks, "Why on earth did I do all that for him?" At the same time, they're completely co-dependent and really love each other.

Why do you think Stewart and Freddie bicker so much?

It's a modus vivendi for them. Some couples do work like that. It's somewhere they both feel safe tilting at each other. Although the lances generally don't penetrate, just occasionally a few splinters get stuck. Every once in a while, there are a few tears from Stuart.

Do you believe that Vicious is a courageous commission?

We're asking the audience not to laugh at these characters because they're gay or old, but because of their relationship and their views of themselves and the world. The fact that there are two older gay men is incidental. But at the same time that is one element which makes this unique. It's not our brief, but this could well help to change people's minds.

Have you got a lot out of the studio audience?

Definitely. It's essential. You have this great feeling being on stage. It gives you a huge adrenaline rush which you might not get otherwise. I get nervous beforehand, but once you're on stage, the studio audience really gives you a buzz. It's a wonderful thrill.

What are the benefits of pairing you with Ian?

A great deal of the work was already done. We didn't have to use up valuable time getting to know and like each other. That was already a given. We started from the point of view of being very happy in our mutual skins. It's been a delight collaborating with Ian.

What do you like about Gary Janetti's writing?

It's really special. It's a unique combination of reality and truth and gags. The characters are identifiable people, and the gags work so well because they're based in reality. We are there to make people laugh, and I think we succeed in that because, above all, Vicious is really funny. It's been a joy to work on.