When Dave discovers Calvin hasn't seen a physician in nearly a decade, he insists the Butler patriarch schedule a physical stat. But Calvin gets more than he bargained for when Dr. Fisher insists he undergo a routine colonoscopy.

Concerned about the safety of a treehouse Calvin's building for Grover, Dave recruits Marty to supervise covertly. Also, an innocent mistake on Malcolm's part leads to a heated bake-off between Tina and Gemma.