People.com's Halloween Party

Before They Were Stars: Halloween Costumes!

See Carrie Underwood as a bunny, Nick Jonas as the Blue's Clues pooch and more stars when they were still trick-or-treating!

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GREG GRUNBERG

"My favorite Halloween was dressing up like the Village People with my oldest and best friend [Lost producer J.J. Abrams, right]"," says the Heroes star, here in 1980. "I still can't figure out which member of the band he was trying to look like!"

Boo! Hollywood's Real Ghost Hunters!

Boo! Hollywood's Real Ghost Hunters!

Is Leighton a fraidy-cat? Does Anna believe in ghosts? Find out who jumps at things that go bump in the night!

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