There is a similarity in the faces of all great comedians. From Charlie Chaplin to Robin Williams to Jim Carrey, men who traffic in humour all have facial features that are etched in paradox. They are all good-looking, but in a strange way. They all look happy, but also sad; smart but also stupid. Although Martin Freeman may not be as famous as Chaplin, Williams or Carrey, he does share this facial idiosyncrasy. The best way to describe his face is, well, squidgy. One would suspect his cute and squidgy face is the reason he is always cast in funny roles.

"What the f*** is that about? I've got a funny face?" Freeman asks, feigning incredulity, clearly getting a perverse pleasure out of the comment. "I wonder how often Brad Pitt gets that? I'm guessing never." The actor is in the city for the Toronto International Film Festival to promote the Rembrandt biopic in which he stars. Freeman admits he was puzzled when he first received Peter Greenaway's script but there is no doubt that he was relieved to finally be seen as someone other than Tim.

"A lot of people think I'm a comedian, but I've never been a comedian, I've never done stand-up or anything like that," Freeman says. "In 1998-99 [I was doing] BBC shows and theatre that were funny and people suddenly wanted me to be funny, which I really enjoyed, but still, in my heart, I'm just an actor." Freeman's career started out in the same way as most other young British actors. He graduated from drama school, appeared in several theatre productions and made his way into the cast of long-running TV dramas like 'Casualty' and 'The Bill.' Then, in the early '00s, he became a staple of BBC comedy series like 'Bruiser' and 'World of Pub.' But his big break arrived in 2001 when he was hired as witty slacker Tim Canterbury in a new BBC show called 'The Office.' Ricky Gervais' comedy became an international hit and ushered in a new TV genre - the comedy of embarrassment.

The only downside to 'The Office' becoming such a cultural phenomenon, is that the show as a whole threatened to eclipse the actors within it. But watching Freeman embody Rembrandt in 'Nightwatching,' one realizes how talented the actor truly is. Despite the alienating dialogue and staid set design, Greenaway's film teems with life as the actor sheds all trace of his 'Office' alter ego and breathes life into the 17th century painter.

"I was trying to make him as real as possible and as relevant as possible, not so that you're seeing Rembrandt, the great old tortured genius, or Rembrandt, this unattainable figure," Freeman says of his portrayal of the artist. "Rembrandt did all the same things that we do and a lot of the time for the same reasons that we do, i.e. to pay the rent and feed his family."

Freeman plays the painter with an unexpected intensity but the role is not without humour, which the actor says is essential to any realistic characterisation. "There are funny moments in 'The Godfather' and there are tragic moments in Laurel and Hardy," he says. "No one you know has never ever been funny and never been serious or maligned or tragic. That, for me, is what acting is."

Although he would rather be known for his role in 'Nightwatching,' Freeman is not one of those actors who refuses to acknowledge the source of his fame. "Not many things take off the way 'The Office' did," Freeman concedes. "In my country I could probably name three things in the last ten years that have culturally made that sort of impact. Very few things are going to hit - for any reason, for whatever luck, for whatever fate - like 'The Office' did."

Greenaway's intellectually alienating film will surely not be the thing that persuades audiences to divorce Freeman from his 'Office' role. Hopefully, 'Nightwatching' will, however, help filmmakers see beyond Freeman's squidgy face.