It's Walker's birthday and Geri is pulling out all the stops; Walker, Capt. James and Trey tackle a case together; Cassie surprises everyone with her return; Abby asks for Liam's help to bring Stella out of her cocoon.

Walker, Cassie and Trey are charged with keeping acerbic Maybelline safe; Cassie grapples with a big decision and seeks out Geri; Liam tries to help Stella move on; August wants to join an after-school program and asks Bonham for support.

Trey and Liam try to help Walker with Geri; Liam aids Cassie in sifting through the clutter and tells Walker that he's worried about Stella; Stella and Sadie look into recent events; August's bootcamp training is not what he expected.

Walker's lies about the Jackal case finally catch up to him and test his friendship with his old partner Captain James; Cassie works a lead in the Jackal case with Detective Luna and learns a hard lesson; Stella has a shocking realization.

Walker, Trey, Cassie and Detective Luna are all hands on deck with their case; Liam jumps in to assist Geri with an interesting offer; Stella and August help Abby and Bonham and uncover something intriguing; James tries to make amends.

Walker, Trey and Cassie prepare for what Captain James has in store for them at HQ; Stella and August start to put some pieces together; Walker makes plans for his future and Liam questions his brother's motives.

Walker, Trey, Cassie and Detective Luna explore more leads; Captain James notices Cassie and Luna growing closer; Stella goes to Bonham for self-defense training and August excels in boot camp training; Bonham and Abby discuss the future.

Liam expresses his concerns about Walker to Trey; Captain James asks Walker to take a break; Stella searches for the necklace; August needs Walker's help with a project; Cassie and Detective Luna take their relationship to the next level.

James, Cassie and Trey appear to make some headway in their investigation; Stella and August make a startling discovery; Bonham and Abby have differing views about their retirement plans, with Liam serving as a referee.

Walker sets out on a new mission; August opens up to Geri and Liam; Bonham notices that something is off with Abby; Luna introduces Cassie to an old friend, and things don't go as anticipated.

Cassie, James, Trey and Luna start to put together the pieces of the Jackal case. Meanwhile, no one has heard from Walker.

Geri is upset with Walker for not opening up to her; Cassie, Trey and James conduct more interviews; Bonham and Abby realize that they both need to give a little with their plans for the future.

Walker wants to be what Geri deserves; Captain James advises Cassie and Trey, who have their final lieutenant interviews; Stella and Liam discuss her future; Bonham and Abby admit what they want; August graduating brings everyone together.