Cursed (2005)

It is a moonlit night in Los Angeles, when something lurking in the shadows causes their car to suddenly swerve off the road and a teenaged brother and his career-driven sister emerge relatively unscathed, but forever changed by the accident. Suddenly, the siblings find themselves blessed with increased physical strength, heightened sensibilities and undeniable allure to everyone around them. But, what if what happened to them that night wasn't just an accident and what seemed like fate was really something more?

Official website: http://www.miramax.com/cursed/