The Fosters kids attend a party at the Derby warehouse, but things escalate quickly when the cops show up. Lena struggles when Stef starts to become obsessed with an ongoing case at work, meanwhile Brandon's relationship with Grace is put into jeopardy with Courtney back in his life.

Lena's parents are back in town for a visit, while Callie and Aaron get closer than ever before. Mariana tries to get closer to Logan, but it backfires when his girlfriend catches wind of it.