Mariana tries to innocently get closer to Logan, but her plan backfires when Logan's girlfriend finds out. Meanwhile, Brandon's jealous of Courtney and Gabe's budding romance, making him question his relationship with Grace.
Callie is torn with turning over a new leaf or supporting a cause that means a lot to her, while Jude and Taylor begin making gaming videos that earn them unwanted notoriety. Elsewhere, Stef makes major headway in her case.
The kids secretly attend a party at the derby warehouse, but things escalate when the cops show up. Elsewhere, Lena struggles with Stef's detachment from the family, as she becomes obsessed with her detective work bringing down a child molester.
Callie and Aaron discuss taking their relationship to the next level; Mariana finds fulfillment training with the Latina derby team; and Brandon's new girlfriend, Grace, catches him playing hero to his ex-girlfriend, Courtney.
Callie gets control of her life and applies to audit art classes at a local college; Jesus distances himself from Mariana and Brandon so he can build his tree house with Gabe alone; and the Fosters get a new neighbor.
In the Season 5 premiere, Stef frantically searches for Callie after she offers to help Diamond; Jesus struggles with his TBI and unleashes his anger after discovering Brandon helped Emma with a deeply-personal decision; and protests continue over Anchor Beach Charter's privatization, with Mariana leading the charge.