It’s not often that a film festival is described as a lifeline, but for Paul Bettany that’s what the Toronto Film Festival turned out to be. His latest film, Creation, a biopic of Charles Darwin in which he plays the scientist, was the opening gala and had some great reviews at the event — one of the first stops on the pre-Academy Awards circuit, alongside Venice. He was there with his wife, the Oscar-winning American actress Jennifer Connelly, who plays Darwin’s deeply religious wife, Emma.

It was their first full acting collaboration, and the Hollywood Reporter said that Connelly’s portrayal of “anguish [and] undying loyalty” and Bettany’s “nuanced performance . . . should attract awards attention”.

“I think people began to see there might be some sound financial reasons to back the movie,” Bettany says of Toronto, now that he’s back in London. He admits that Creation had some trouble securing a North American cinema distributor, as did his last film, The Young Victoria — another British historical film.

Indeed, it’s not just the central characters that may give pause to “foreign” audiences. Creation is a slow, meandering, occasionally confused film that jumps back and forth in time. But in chronicling early-middle-aged Darwin’s anguish, Bettany is excellent as the genius racked by humanity-shaking insight, grief at the death of his favourite daughter Annie, and by illness. The turmoil as he agonises over whether to publish his blockbuster theory of evolution is writ large on Bettany’s balding, burdened scientist: in its debunking of creationism, On the Origin of Species will, he understands, “kill God”. And, Bettany adds, “rob his wife of her solace”.

“I read the script and thought it was a great part for Jennifer,” Bettany recalls, adding that her cameo as his character’s wife in last year’s children’s fantasy film Inkheart was more “a sweet thing for our kids”, their son Stellan, 6, and Bettany’s stepson Kai, 11. “We didn’t want to pick a romantic comedy in which we rubbed everybody’s faces in how happy we were.” The Victorian costuming covered up the prominent tattoo on Bettany’s left forearm: a rose briar encircling the name of his wife of six years.

The tall 38-year-old actor acknowledges how tempting it is to “fake relationships onscreen by looking longingly at each other a lot. And in actual fact marriages are about ignoring each other a huge amount of the time!” he laughs. “And about your unconscious physicality with that person.” This, then, is not the Darwin of beardy, sea-faring, chaffinch-wrangling legend. The far side of the world, studying flora and fauna? Bettany had been there, sketched that as the nature-loving surgeon in Master and Commander: The Far Side of the World.

In the past few years he has appeared in Hollywood blockbusters (a murderous albino monk in The Da Vinci Code), family dramas (The Secret Life of Bees), rom-coms (Wimbledon), edgy arthouse fare (Lars von Trier’s Dogville, and the Rosamond Lehmann drama The Heart of Me). Next he will play a humanity-saving angel Gabriel (Legion) and a vampire-slaying man of the cloth (the graphic novel adaptation, Priest).

The English actor from a theatrical family seems to thrive on such eclecticism. “I learn from all these different sources. And there’s fun to be had,” he says. “I started reading Shakespeare and Racine when I was maybe 18, and it was mostly to impress girls. Whereas I got my first set of holsters and a cowboy hat and started jumping around shooting people when I was a kid. And at the moment I’m getting to do that in Priest. I would be lying if I didn’t say it was incredibly fulfilling flying around on wire and stabbing vampires.”

Maybe Bettany isn’t as well known as he should be. Certainly he deserves the high-profile parts of such peers as Jude Law and Ewan McGregor. He has proved that he could blaze off in myriad directions at once, in the visceral Britflick Gangster No 1 (2000), in playing a knockabout “Geoff Chaucer” in the medieval romp A Knight’s Tale (2001), and as the figment of Russell Crowe’s imagination in A Beautiful Mind in 2001, (on which he met Connelly, and for which she won her Best Supporting Actress Oscar). “Yeah, but I don’t know if that was a good idea,” he says now.

“In a career way, I just had no . . . strategy,” he says slowly. In some respects this has been his hallmark. He followed a turn in Stephen Daldry’s acclaimed 1992 West End staging of An Inspector Calls with an ill-starred stint with the Royal Shakespeare Company. “That was mayhem. You’re in three plays playing walk-ons, and I was just drunk and high on drugs all the time. I felt like I was going on and shouting in a barn every night: ‘My Lord, blah blah . . .’ I just didn’t get it. It didn’t feel right.” He left after one year.

“So I don’t know if blazing off in different directions was a good idea,” he continues. “But I think it was the only way I could have done it. I don’t have regrets about it. I’m very content with life right now.”

The family splits its time between their Brooklyn townhouse and Vermont retreat: he and Connelly have a rule that their film careers don’t keep them apart for more than two weeks at a time.

He’s hankering after the old country. He’d like to work with Shane Meadows, Andrea Arnold, even maybe nab a part in the forthcoming remake of Brighton Rock.

“I would love to,” Bettany says eagerly. “Something contemporary, something here . . . Yeah, London drama, contemporary, loadsacash, thank you!”

Creation is out on Sept 25

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