After Max just misses running over a fleeing summer camper on the road, Ben, Max and Gwen take the boy back to his nearly deserted camp. It's nearly deserted because a race of alien mushrooms has taken over the camp as their first step for world domination. As Gwen and Ben argue as to whose birthday is more important, (since they both fall on the same day), Gwen's able to rally the remaining campers and Ben discovers yet another alien hero, Wildvine, as they team up to take down the mushrooms.