John Gordon Sinclair: The world turned upside down

John Gordon Sinclair will perhaps always be best known for playing the gauche youth who fancies the schoolgirl footballer, in the 1980s film Gregory's Girl, but he's racked up an impressive list of credits since then. His latest role is Martin Attwood, a somewhat dull academic transport consultant whose wardrobe is "more Debenhams than Ozwald Boateng", in Stephen Poliakoff's Sweet Panic.

"When I read the play I liked the message," says Sinclair who is in his seventh year in the West End. "It is about how people no longer take responsibility for their actions. At one point in the play, the neurotic mother played by Jane Horrocks, Mrs Trevel, can't get hold of the child psychologist on the bank holiday weekend and decides this is the reason why her child ran away," says Sinclair, who last acted with Horrocks 10 years ago, in the West Indies in Alan Bleasdale's TV film Self-Catering. "We have been friends ever since."

Sweet Panic, an intense but humourous urban thriller, is Stephen Poliakoff's first play in London since Remember This at the National Theatre in 1999. More recently, he had a huge success with The Lost Prince on BBC1. Sweet Panic will also be transformed into a feature film for television, starring the theatrical cast.

The calm and measured child psychologist Clare is played by Victoria Hamilton, who recently won acclaim in the West End and on Broadway with her performance as Sheila in A Day in the Death of Joe Egg. "Clare's response to every-thing is always considerate," says Sinclair -until, that is, her certainties about life are brought into question when she is stalked by Horrock's character, the mother of one of her young clients who sets out to destroy her.

"Everything gets turned on its head," says Sinclair. As Clare's husband, the effect of Sinclair's Martin is to undermine her position even further. "She finally realises that not even he is sane. Martin has written this book on the London metro bus, but when he gets to the lecture on worldwide transport concern, there is this German academic who has also written a book on it, and his life's work goes down the pan," says Sinclair. "Martin loses control after that."

Sinclair says that the ideas and language of the play took a little mastering. "The piece has a heightened sense of reality about it - there is a lot of action and jumping around. It is quite abstract. Poliakoff keeps telling us that we need to tame all the ideas in the play before we can really start working on it. It is only after rehearsing it for a while that I started making connections that I hadn't before realised. It's all beginning to make more sense."

The play's conclusion is a message to parents who are driving their children to perform and succeed. "To what ends are they driving them?" asks Sinclair. "Parents set all the standards. But at the end of the day, we don't get it right yet expect our children to."

'Sweet Panic' opens tomorrow at the Duke of York's, St Martins Lane, London WC2 (020-7369 1791)