To many, he will be for ever remembered as the gawky teenager Gregory Underwood, in the 1980s coming-of-age hit Gregory's Girl.
So his fans may be forgiven for blanching when they hear the name John Gordon-Sinclair now being whispered in the same breath as gritty crime writers such as Elmore Leonard.
The star of the romantic comedy has signed a five-figure, two-book deal with Faber & Faber, home of other crime writing luminaries such as P D James and Nicola Upson.
His first book, Seventy Times Seven, is set in Tuscaloosa, Alabama, and Newry, Northern Ireland. Due out next September, it follows a hit man sent to the southern US state by an IRA boss to kill a former IRA mole.
Even Gordon-Sinclair, 49, is surprised at his new career. He says: "I can't believe it. I keep pinching myself. I've just done this film with Brad Pitt – World War Z – and now with this book... I seem to end every sentence with 'no, seriously', as nobody believes me."
He began researching the Northern Ireland "Troubles" in the 1980s, but he insists the IRA only forms a backdrop to what is, essentially, a human story.
"I've never read crime fiction that's made me cry. So I thought I'd like to write the kind of book I'd take on holiday, but which has some emotional content as well."
Although he now works alongside Hollywood A-listers, the Glasgow-born actor says he would give it all up to become a full-time writer. "My dream life would be sitting in a house in the south of France writing another novel. It wouldn't be sitting in a flat in LA waiting to do another movie."