Unlike many of the other young performers in this issue, Ellen Page doesn’t have a No. 1 album or legions of screaming tween fans. The 20-year-old Nova Scotia native is a Serious Actor, and as such, she has already tackled half a dozen roles so challenging they would give even her middle-aged peers pause.

In “Mouth to Mouth,” Page played a runaway adopted by a cult of well-meaning skinheads who loses her virginity a la “Hounddog.” In “Hard Candy,” she courted controversy as a nervy 14-year-old who punishes a would-be pedophile. Earlier this year, she went from vigilante to victim in “An American Crime,” the true story of an Indiana teen who was locked in a basement and tortured.

“It’s not like I’m some sadistic individual that has purposefully sought out dark, dark material. It just often happens to be the characters that have felt the most honest and that I’ve wanted to play,” says Page, who also made time to play Kitty Pryde in last summer’s “X-Men 3.” “The last two films I’ve shot have been comedies or ‘lighter films.'”

First out of the gate is “Juno,” provocative in its own right, in which Page plays a sardonic teen, knocked up by “Superbad’s” Michael Cera, who decides to give her child up for adoption. Simply put, the movie will make Page a star.

“I read the script a couple years ago, and I really connected to this girl,” she says. “She was like a lot of people I know, but branching away from that common stereotype (of shallow, silly teens) in popular media. Pretty much all I wanted was to play Juno — I was kind of obsessive about it.”

And though edgy is the way she likes it, Page admits, “You have to be really, really careful when children and adolescents are being thrust into intense situations, because as much as acting isn’t real, it’s not exactly make-believe. You’re going to those places in your heart and in your mind.”

Recent breakthrough: Roger Ebert raved of her “Oscar-caliber” turn in “Juno.”

Role model: “I’m a massive Sissy Spacek fan. I mean, ‘Badlands’? Ridiculous! I think maybe you had to be a teenager in the ’70s to have a career like that.”

What’s next: Laffer “Smart People” next spring. Waiting for the greenlight on lesbian werewolf movie “Jack and Diane.”