Autistic since birth, 28-year-old Molly (Shue) is a carefree young woman with an incredible zest for life. Her brother Buck (Aaron Eckhart), a 32-year-old with a full social calendar and a booming career, has had little contact with Molly over the years - until the facility that cares for her closes down. Now it's up to Buck to take his sister in... and that's turning into a full time job! Bold, childlike and very energetic, Molly completely envelops her brothers life and turns his ordered world into chaos. Then, just when Buck is at his wits end, Molly becomes a candidate for a new medical procedure that could cure her completely... but is it worth the risk? Molly sure thinks so... she's ready to experience everything!