People.com Halloween Party

Silly, Sexy, Cool : Star Halloween Costumes!

From Mariah's naughty firefighter to Kim's Wonder Woman, see how celebs reveal their alter egos

JASON PRIESTLEY & FAMILY

The actor went back to his Canadian roots, dressing up as a mountie with his family, wife Naomi Lowde-Priestley and daughter Ava, then 1, at the 2008 Dream Halloween bash, held at the Barker Hangar in L.A.