TORONTO—As a rule, in film, vampires are treated as metaphors for the human condition. Only Lovers Left Alive (opening Friday [April 25]) follows that rule, only more so. It’s a Jim Jarmusch film, after all, and it smacks of the AIDS crisis, the ’70s rock scene, junkies, and the idea of an artist as an all-seeing, eternal observer of history. When Tom Hiddleston, the young Brit actor who plays Tilda Swinton’s lover in the film, met the Straight at the Toronto International Film Festival last fall, he also weighed in on what it all might mean.

“I understand vampires have always been an emblem of passion and sexuality. They’ve become a very potent symbol for the part of human instinct that thrives off blood,” said Hiddleston, adding that he watched a lot of cinematic vampires—in Francis Ford Coppola and Bela Lugosi versions of Dracula, Nosferatu, but not Twilight—to prepare for the role. “I also knew that we were inventing our own mythology in a way. Jim is so smart about vampire lore, subverting and reinventing the genre in his own way.”

In their film, Hiddleston continued, the vampiric urge is about mortality above all. “Vampires live forever, so what if we did too?” he asked. “The way we construct our view of love and relationships as human beings is framed by a spoken or unspoken idea of death—so what if we weren’t going to die? How would that change our commitment to each other? And how would we use our time together? The question that Tilda and Jim and I loved answering was this idea that love’s endurance is an extraordinary thing, and the greatest and only legacy.”

Certainly, the fact that the only lovers who are left alive are Swinton and Hiddleston, shot in languorous chiaroscuro on location in Detroit and Tangier, adds to the film’s appeal.

The young British actor has already made a name for himself in various Kenneth Branagh productions, and most recently starred as Loki in Marvel’s Thor and The Avengers. But his long-limbed, longhaired Detroit rock-demigod pose in Only Lovers should shop his charms to a whole new demographic. Hiddleston admitted, meanwhile, that he would have said yes to any Jarmusch project, citing the Johnny Depp vehicle Dead Man as his favourite film by the director. (“I know for a lot of people it’s Down by Law or Mystery Train, but it’s because it’s so poetic, and the soundtrack is most amazing.”) He said the director spoke to him and Swinton at length about their characters.

“Jim wanted these characters to be refined, poetic, and sophisticated, because they are quintessential artists, but they’re also feral. Animals. They’re wild,” he said. “There were these nights—I was gonna say days, but it was always nights—where we would be on a very limited crew, with just Jim and the camera and sound guys, and we would go out. I would walk around the city on my own, and I felt like a wolf, prowling around Detroit.”