Kieran Culkin Steps Out of Brother's Shadow

Sept. 19 -- Kieran Culkin won't be called Macaulay's little brother for too much longer.

With Igby Goes Down opening nationally this week, the younger Culkin is poised to step into the spotlight. Some critics, including ABCNEWS' Joel Siegel, are already hailing the movie as the next great coming-of-age film.

Culkin plays Igby Slocumb, a 17-year-old rich kid who bounces from one private school to the next. His mom is a controlling, pill-popping tyrant. His earliest trauma is watching the meltdown that led to his father being committed.

Igby is carted off to a different sort of institution — a military academy — where fellow cadets cast him as an oddball and pummel him in the latrine with broomsticks, chanting "Igby goes down."

That's when Igby decides his only hope for survival is to run away, and suddenly he becomes an updated version of Holden Caulfield in J.D. Salinger's The Catcher in the Rye.

"Igby got to see how the world around his father kind of crushed him, at least through his eyes, and that's what's going to happen to him if he stays with his family," says Culkin.

The Secret Lives of Lost Toys

Soon he is hiding out in downtown Manhattan with his godfather's mistress and her grungy bohemian pal. "She's a dancer who doesn't dance, and her best friend is a painter who doesn't paint," says Igby. "It's like a boho version of Island of the Lost Toys."

Culkin's best moments are when Igby's dripping with contempt for his castrating mother, whom he refuses to call "mom."

Weighing several nicknames that seem apropos, Igby says, ""Heinous One' was a bit cumbersome, and 'Medea' was already taken."

"It's so twisted and it's so original," says Susan Sarandon, who plays authoritarian mom Mim Slocumb.

"If the kid in the end had succumbed and become a basket case, I wouldn't have been interested," she says. "I guess it's a little like American Beautiy in that the kids know so much more than the adults."

Kieran Defends Culkin Clan

Culkin, who turns 20 later this month, is quick to shoot down any comparison between his family and Igby's, though that might be inevitable.