Getty

Nat Wolff Has A Confession To Make About Cara Delevingne

Before she was cast in 'Paper Towns,' he didn't know who she was.

In the upcoming film "Paper Towns," Nat Wolff's character Quentin may be obsessed with Cara Delevingne's Margo Roth Spiegelman, but, in real life, the actor admits that he didn't initially know who Delevingne was.

"This is going to sound crazy, because she's the biggest super star in the world -- I had never heard of her," Wolff told MTV News. "She just came in to audition and she was unbelievable. I think she's that character. She's perfect for that role."

Related: Nat & Alex Wolff Are All Cats, Beards, And Feelings On These Brand-New Songs: Listen Now!

"Paper Towns" is the second John Green novel to become a film -- following close on the heels of smash-hit "Fault In Stars" -- and pulls together a lot of the same team from that film: Wolff (who played a supporting role in "Fault"), as well as Scott Neustadter and Michael H. Weber, who co-wrote both “Fault” and “The Spectacular Now." Delevinge's casting was announced in September, and, although shooting starts soon, only she and Wolff's roles have been unveiled.

"Paper Towns" picks apart the idea of the "manic pixie dream girl" (a term coined by critic Nathan Rabin, who recently apologized for its existence) -- zeroing in on a boy named Quentin's obsession with free spirit Margo Roth Spiegelman. Former childhood friends, the two occupy separate social spheres until Margo plucks Quentin from smart-boy obscurity to go on a night-long mission of revenge against an ex-boyfriend who cheated and some wayward friends. When tomorrow dawns, however, Margo has disappeared, and Quentin sets out on a quest to find her -- putting himself in her shoes in order to better understand his dream girl.

Check out Wolff speaking on "Paper Towns" more above -- as well as some pretty unorthodox costuming ideas.