Stef Foster, a dedicated police officer, and her partner Lena Adams, a school vice principal, have built a close-knit, loving family with Stef's biological son from a previous marriage, Brandon, and their adopted twins, Mariana and Jesus. Their lives are disrupted in unexpected ways when Lena meets Callie, a hardened teen with an abusive past who has spent her life in and out of foster homes. Lena and Stef welcome Callie and her brother, Jude, into their home thinking it's just for a few weeks, until a more permanent placement can be found. But life has something else in store for the Fosters.
Stef frantically searches for Callie after she offers to help Diamond, thinking she has nothing to lose after accepting the plea deal. Struggling with his TBI, Jesus unleashes his anger after discovering Brandon helped Emma with a deeply personal decision. With Mariana leading the charge, protests continue over Anchor Beach Charter’s privatization.
Callie gets control of her life and applied to audit art classes at a local college. Jesus distances himself from Mariana and Brandon so he can build his treehouse with Gabe alone. The Fosters get a new neighbor.
Callie and Aaron go on their first official date. Mariana and Jude spearhead an underground school newspaper. Noah and Jude question their compatibility, while Brandon and Grace take their relationship to the next level. The moms have their new neighbors over for a family dinner party.
Callie and Aaron discuss taking their relationship to the next level. Mariana finds fulfillment training with the Latina derby team. Brandon’s new girlfriend Grace catches him playing hero to his ex-girlfriend Courtney.
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.
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. Stef makes major headway in her case.
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.
Brandon throws a party which turns south when secrets are revealed. Mariana and Jude try to convince the students to vote against their school going private.
It’s prom night at Anchor Beach. Grace’s mom has a candid conversation with Brandon, meanwhile Ximena faces a life-altering decision when ICE agents show up at prom.
Ximena and Callie are still in the church seeking sanctuary from ICE. The Adams Fosters’ offer support to the Sinfuego family as they struggle with their immigration status.
Callie actively helps to make Ximena’s fight visible. Meanwhile, Brandon and Grace struggle to be intimate knowing her diagnosis and Mariana is suddenly courted by multiple suitors.
Callie and her friends support Ximena in a big way at a conservative anti-immigration rally and get a lot of buzz for Ximena’s plight. Meanwhile, an unlikely source offers a key piece of evidence that may help save Anchor Beach from going private and the family celebrates Stef’s birthday.
Brandon and Grace plan the ultimate senior prank which ends up going a little too far. Mariana and Mat make a huge decision about the future of their relationship.
Callie receives a surprising tip from an unexpected source. Meanwhile, Jude tries to assuage Noah’s fears about his budding relationship with fellow gamer Declan.
Stef’s mom comes to visit and helps Stef cope with a tough time. Meanwhile, Callie and Jude grapple with the memory of their biological mother.
Stef confronts her demons and finally comes clean to Lena about what’s been troubling her. Mariana and Emma find themselves going head to head, putting Poppy and Jesus in an awkward position.
Callie speaks on a panel about Ximena’s struggle and realizes she may have a passion for something other than art. Meanwhile, Mariana is torn between two suitors.
Brandon and Grace go on a road trip and discover a lot about each other, while Mariana and Emma vie for a competitive internship. Stef and Lena go on a couples retreat to reconnect.
It’s graduation day for Callie and Brandon, but after some shocking news, the family wonders whether they will make it to the ceremony.
One year later, the Adams Fosters comes together for some major celebrations.
The family travels to Turks & Caicos for Brandon and Eliza’s wedding where they find themselves at odds with their future in-laws, meanwhile when Brandon and Eliza find themselves butting heads, Brandon turns to the person who knows him best.
After a turbulent few days in Turks & Caicos, the family starts to question if the wedding will actually take place. The moms make a huge decision that will change the family forever.