David Clark is a small-time pot dealer who likes to keep a low profile. His clientele includes chefs and soccer moms, but no kids. He learns the hard way that no good deed goes unpunished when he tries to help out some local teens and winds up getting jumped by a trio of gutter punks. Stealing his stash and his cash, they leave him in major debt to his supplier, Brad. In order to wipe the slate clean—and maintain a clean bill of health—David must now become a big-time drug smuggler by bringing Brad's latest shipment in from Mexico. Twisting the arms of his neighbors, cynical stripper Rose and wannabe customer Kenny, and the tatted-and-pierced streetwise teen Casey, he devises a foolproof plan. One fake wife, two pretend kids and a huge, shiny RV later, the "Millers" are headed south of the border for a Fourth of July weekend that is sure to end with a bang.