In the season premiere, Alec (ADRIAN PASDAR) is in jail after his arrest for murder, but he still manages to unnerve Emma. Rebecca and Sutton formulate plans for the Mercer family.

Sutton steps up her plans to win back Ethan. Feeling left out of Emma and Thayer's (CHRISTIAN ALEXANDER) growing closeness, Mads shocks Emma with a family revelation.

Sutton decides she wants her life back in order to spend more time with Ethan, and Laurel asks Jordan (recurring guest star RYAN ROTTMAN) out on a very awkward date.

Rebecca uses Sutton to further her agenda, and Emma learns that Sutton may not have told her the whole story about the night her car went in the lake.

Laurel begins asking questions about Sutton's radical personality changes and Emma renews her search for her birth mother.

The school formal creates new opportunities for secrets and lies to be revealed when everyone ends up with the wrong partner. Emma turns to Ethan for help.

Emma struggles to make sense of newfound revelations and shifts in her relationships with Ethan and Thayer (CHRISTIAN ALEXANDER). Sutton and Rebecca's bond may start to crack.

Everyone gathers to celebrate the wedding of Dan (TYLER CHRISTOPHER) and Theresa (YARA MARTINEZ), but the celebration does not go off as planned. Ethan confronts Emma.

Ethan's confession to Dan (TYLER CHRISTOPHER) threatens their relationship. Sutton gets a phone call that may provide valuable information. Emma's feelings for Thayer are tested.

In the season finale, growing suspicions have everyone on edge. Dan (TYLER CHRISTOPHER) gives Ethan an ultimatum with heartbreaking consequences and Emma finally confronts Rebecca.