The Coterie Crew deals with the fallout of the season three finale. Tommy Sung's trial comes to a close, and Callie needs to keep Kathleen from legal trouble. Malika processes Isaac's surprise return. Gael tries to keep Isabella in town. With the approval of the Fight Club Girls, Mariana meets with Evan. Alice is on the road, leaving Sumi as acting manager. Someone new moves into the Coterie.
Taking place a few years after the events of The Fosters, Adams Foster siblings Callie and Mariana relocate to Los Angeles to begin the next phase of their lives. As they move into a communal living apartment building called The Coterie, Callie becomes a law clerk working for Judge Wilson while Mariana becomes a software engineer. The two of them navigate their young adult lives while interacting with their neighbors and the people they befriend.