Artie and Diane agree to look after their three grandkids when their type-A helicopter parents need to leave town for work. Problems arise when the kids’ 21st-century behavior collides with Artie and Diane’s old-school methods.

Pressured by a greedy uncle (Brian Cox) and a pile of debt, lovable loser Steve Barker (Knoxville) resorts to an unthinkable, contemptible, just-crazy-enough-to-work scheme. He pretends to be mentally challenged to rig the upcoming Special Olympics and bring home the gold. But when Steve’s fellow competitors get wise to the con, they inspire him to rise to the greatest challenge of all: becoming a better person.