The all-American dad

Gruff, grouchy, with a weakness for beer and unrefined soft furnishings, Mahoney's Martin Crane exuded that air of naturalness which always makes you think it can't have been much of a stretch for the actor.

Turns out that it was. Not only is Mahoney not a dad, he isn't even an American. Mahoney spent the first 19 of his 65 years in Lancashire before following one of his seven siblings out West, where he set about removing all evidence of Manchester from his voice.

He never quite managed to erase the lot. "There are words that still give me away," he says. "We were doing an episode of Frasier and I had to say, 'See you next Wednesday.'" He pronounces the word with a hard D. "The director said, 'See you when? Next what?' They wanted me to say Wensday. It was so alien that I couldn't do it. So they changed it to Tuesday."

Another thing not widely known about Mahoney outside his adoptive Chicago is that he is a committed stage actor. He has been a member of the prestigious Steppenwolf company ever since John Malkovich asked him to join in the late Seventies, and has done more than 30 plays for them, including a production of George S. Kaufman and Moss Hart's 1939 comedy, The Man Who Came To Dinner, which had a successful run at the Barbican Theatre.

That was his British debut, and for seven years he has longed to come back. But if you're in a hit show that takes eight months of the year to film, it's impossible to do more than one play a year. But Frasier finally came to an end after more than 260 episodes and 11 long seasons last year. He has scarcely stopped doing theatre since.

Romance, the new David Mamet play at the Almeida, will be his third play on the trot, and there are two more scheduled for next year. "Frasier made me financially independent. I don't have to do anything except what I want any more, which is small theatre."

Romance, which premiered off-Broadway earlier this year, calls for strong stomachs in both cast and audience. In a ribald courtroom farce, Mamet tilts his lance in every direction.

A prosecutor is edging out of the closet. A Jewish defendant and his goy attorney lock horns with spectacular abusiveness ("you people can't order a cheese sandwich without mentioning the Holocaust"). Meanwhile, the judge is prey to drug-induced mood swings and, halfway through the play, admits that he once abused his daughter.

"He is a pill-popping sexual predator," says Mahoney, who plays him. "He has a law degree but some of the dumbest people I know have law degrees. He doesn't belong in this job, has all this power that was given to him probably though political favours, and has no idea what he is doing. I hope to God he's not typical of American judges."

The industrial quantity of salty language is not really Mahoney's thing. "I was never a badlanguage person. I have to be really angry about something and then it'll come out. It would be trying to get through on a telephone when all you can get is a recorded voice. That'll get me going. Or extreme frustration. When I come to rehearsal and I can't remember a line all of a sudden I'll go 'Mother F***ER!'. But at myself. I've never called anybody anything like that."

Mahoney's background was working-class - his father was a baker. America, where an older sister had emigrated as a GI bride, must have seemed like the promised land. He compares his Atlantic crossing - he fetched up in Illinois where his sister had settled - to a move from black and white into technicolour. But it took him a long time to get going.

After the army and college, he taught English literature, edited a medical journal and generally felt unfulfilled until he enrolled in an acting course at 37. The course was run by William H. Macy and David Mamet. He turned out to be such a natural that he got a part in Mamet's next play.

"Then I did a couple of his one-acts on radio. So I know him pretty well, but I wouldn't call myself a good friend." He has never married. The one thing he misses about Frasier is the company of friends.

"I think we had taken the show about as far as it could go. Kelsey [Grammer] always said, "We will never ever speak down to our audience. We will always assume that anybody who watches us has a brain in his head.

"And so we never did, except towards the end, I think, because we had no more stories to tell we sort of slipped a little bit. I was glad it ended and I was glad to leave LA. I don't hate it but it wasn't my home. I wanted to get back to Chicago."

Working in the country of his birth is another sort of homecoming. "England is like your parents or something. You just want to please them. You want their approval. It's like the old New York song: if you can make it here, you can make it anywhere, and that's the way I feel theatre-wise about England."