Beleaguered Philip Davis (James Wolk) is sent at his father's behest to place his eccentric grandmother, Estelle (Cloris Leachman), into an assisted living facility. To add to his troubles, his small-time drug dealer sister Megan (Mickey Sumner) decides to join him, using the trip as a cover for a large marijuana buy. When Estelle discovers her grandson's plan, she furiously takes off for Seattle, unaware that her granddaughter's drug haul is stashed in the trunk of the car. The estranged siblings have no choice but to go on the road after their wayward grandmother, the taxidermist dog she keeps as a companion, and five pounds of marijuana.