While Calvin is cooped up at home recovering, he begins spying on his neighbors from the window. He comes to believe that something sketchy is going on across the street, so the whole crew helps him figure out how to catch their new neighbor in the act.

Gemma and Tina are at odds with one another and Dave and Calvin try to bring them back together. Meanwhile, Marty is sick and not handling it well, so Malcolm fills in for him and goes to a baby class with Courtney.