I went through a tricky patch at school. I was one of those people who was slightly on the outside of each group. I could get into groups temporarily, but I was not a member of them. I was a kind of roving member.

I went to Cavendish School in Hemel Hempstead. I was a bit geeky and did not fit in. I was quite buttoned up, the girl with her top button done up, and I was very conscious of the rules. I was not bonkers or daft, I just felt a bit nervous.

I was never bullied. I was a bit like an invisible person. I never found myself on the games field or being cool, smoking behind the bike sheds. I could not quite work out where I belonged, but it’s that old thing when you find you can do voices and mimicry and plays and everything is OK.

I was about 14 or 15 when I really found the freedom of that lovely dark studio, with curtains and lights. It was a block where you could be someone else and say what you can’t normally say.

It is so corny that I almost can’t say it, but I felt at home as soon as I got there. It was a comforting place where I could pretend to be someone else. Once I discovered drama I found my little niche and I was quite happy.

I concentrated all my efforts into drama and I got what I needed in terms of qualifications. I was not that focused in my other subjects because I knew very early on that I wanted to go to drama school.

I did have good teachers, and there were several I can think of, but one in particular was Roger Clay, my drama teacher. What was so good about him was that he provided space and he took it seriously and he took me seriously. When I said I wanted to be an actor he did not say I must go off and be a teacher. I really appreciated being taken seriously. It is a very, very special thing for a teacher to do that.

He loved his subject. He took us to the theatre - I did not come from a family that went to the theatre - and he introduced me to Foyles bookshop, where I used to spend hours looking at plays. We did a trip to Evita and that did it for me. There was a visit to Foyles bookshop thrown in and that started the endless sitting on stools looking through plays for suitable parts. I still do that, although mostly in Waterstone’s now. I loved the whole madness of Foyles, the ritual of it, and the way you could just sit there looking. Even if he had just given me that it would have been worth it.

He organised competitions, readings and plays and he was so energetic about it. We had a stage in the studio and there was always a play going on. We did a huge production of Godspell, which is great for young children, with all those lovely, mad costumes. He was good at mobilising everyone. Everyone would be there.

We did a play called The Down-Going of Orpheus Hawkins, which was about Orpheus in the underworld. They added an extra part to it - the critic - that I did. I came on as this character commenting on the action, like an extra narrator. Then we did Godspell and Dark Side of the Moon and a lovely production of Volpone.

I was still a bit of an outsider, but it no longer mattered because I had drama. I have always loved the fact that you are in it together and the camaraderie of everyone doing the plays. It was a cross-section of the school: the cool people, the geeky people, the people in the middle. It did not matter where I was any more.

• Claire Skinner has appeared in the Mike Leigh films `Naked’ and `Life is Sweet’, as well as TV series `Life Begins’ and `Outnumbered’. She is currently appearing in `Trinity’ on ITV2. She was talking to Nick Morrison.