Lily Cole already has a fan in Terry Gilliam

Though “The Imaginarium of Doctor Parnassus” will probably always be known primarily as the last film for actor Heath Ledger, it may someday also be recognized as the first real film role for Lily Cole.

The 21-year-old British-born Cole already has been one of the world’s top models since being discovered at the age of 14. With her distinctive wide-set eyes, tiny button mouth, porcelain-pale skin and bright red hair, there is something ethereal, almost alien about her, an in-built strangeness that director Terry Gilliam set to full use in “Parnassus,” which opened in Los Angeles on Christmas Day and will expand to theaters nationwide on Jan. 8.

“That’s why I cast her,” said Gilliam. “I’ve got an instinct for that sort of thing. ‘Boy, this is an extraordinary creature there.’ No matter what’s going on, you’ll be watching her.”

Cole brings a surprising well of emotional tenderness to her part as Valentina, the daughter of an aging street performer (Christopher Plummer as Parnassus) locked in a long-standing battle with Mr. Nick (Tom Waits), the devil himself. As Valentina’s 16th birthday approaches, her father frantically tries to save her from Mr. Nick’s clutches, even as her own affections become torn between a shady hustler (Ledger) and a fellow member of their performance troupe (Andrew Garfield).

Cole, raised by her single mother alongside two siblings, first gained international attention in 2003 when she appeared in Vogue. Since then, she has graced the pages of other top fashion magazines and walked in runway shows for Chanel, Alexander McQueen and others. In 2004 she was named model of the year by the British Fashion Awards and has been included on the Sunday Times Rich List as one of Britain’s wealthiest young people.

Even some relative pans of the film have found time to take positive note of Cole, such as when the New Yorker’s Anthony Lane declared that her “unearthly heart of a face is like a special effect.”

Cole appeared previously in a small role in the private-school farce “St. Trinian’s,” which she said she took simply to spend some time on a working film set. She was also cast around the same time as “Dr. Parnassus” in the Sally Potter film “Rage.” It is her part as Valentina that she considers her first real piece of screen acting, done in the company of seasoned actors such as Ledger, Plummer, Garfield, Verne Troyer and the trio of actors who completed Ledger’s role after he died: Johnny Depp, Jude Law and Colin Farrell.

“Is there a polite way to say green?” Cole noted when asked how she fit into such rarefied company. “ ‘Were you humbled and terrified?’ Yes, I was. I auditioned for the role fearlessly and naively, just enjoying a conversation with Terry, and when I got offered the part and got closer to shooting I realized more and more what I was getting myself into.

“I remember especially a first kind of read-through; it was me, Heath, Christopher, Andrew, Verne [Troyer] and Terry and [cinematographer] Nicola [Pecorini]. I remember in that room realizing, ‘Whoa, these people are really talented and really experienced.’ It was a wonderful place to be in, but I was also completely intimidated by who I’d have to play against. I voiced that to Terry a lot before we started, but for whatever reason he made that leap of faith and had that instinct that he wanted me to play this role.”

This is not the first time that Gilliam, veteran director of such films as “Time Bandits,” “Brazil” and “Twelve Monkeys,” has cast a young model in one of her first acting roles. He cast a then-teenage Uma Thurman in one of her earliest roles for his 1988 film “The Adventures of Baron Munchausen.”

“She and Lily have a lot in common,” Gilliam said. “They’re both incredibly intelligent, they’re both very confident because they both started modeling and traveling the world when they were very young. So they’ve been around a lot of stuff, and they know how to protect themselves. There’s a bearing there that, even when they’re not certain, they can hold themselves up against whatever’s been thrown at them.”

It is, of course, the January 2008 death of Ledger by accidental drug overdose during a break in production that has long been the best-known aspect of “The Imaginarium of Doctor Parnassus.” The film was re-conceived slightly to allow three additional actors to complete Ledger’s role -- within the story the character passes through a magic mirror that reconfigures his appearance -- but Gilliam maintains the story was altered less than one might imagine.

“We didn’t change much at all,” he said. “It’s basically exactly as we wrote it except for about three scenes. That’s it. I think that’s the dangerous thing of talking about it, if I make too much of the difficulties of salvaging it, then people think it’s not the film I wanted to make. But it was really simple; it was pretty easy and very pragmatic.”

For Cole, who had flown to New York City from London with Ledger just days before his death, the intrusion of such a harsh reality on Gilliam’s fantasy world set the entire production on an emotional back burner.

“It took me a while to even think about the film,” Cole said. “And when I did I wasn’t even thinking about the practicalities of whether they could actually finish it, creatively how could you finish it, but rather I was thinking, ‘Should they?’ Initially, I was torn.”

With the long journey of “Doctor Parnassus” finally winding up, Cole has moved on to other projects. She has already shot a small role for an upcoming Roland Joffe film and early next year will be filming a part in Mary Harron’s “The Moth Diaries.” She has also been studying art history at Cambridge University. All of this is part of her hope to build a life beyond the catwalks and photo shoots.

“The reason I’ve maintained an interest in school and made these films is to do what I’m interested in doing,” said Cole. “I take opportunities as they come. . . . Hopefully I can fill my life with things I like doing.”