Tensions run high when Walker and Liam investigate a cold case together. Micki, still on desk duty, is working through her grief while slowly easing her way back into the field. Trey tags along for a fishing trip and gets a lesson on love. August makes a discovery that could lead to answers about the feud between The Walkers and The Davidsons.

Micki comes clean to Trey about her past and they question what it means for them in the future. After a heartbreaking talk, Micki realizes it might be time to start a new chapter. Meanwhile, Walker and Liam put their differences aside and agree to trust each other when Denise asks them to investigate a case. Bonham dresses up as Santa Claus for the annual holiday party.

When he hears that Serano is out on bail, Dan panics and asks Liam for help. Liam doesn't trust Dan but Dan makes him a tempting offer that would put Serano behind bars for good. There is just a small catch - Liam can't tell Walker what's going on. Meanwhile, Geri decides to have an open mic night at the Side Step and encourages August to hit the stage.

A feisty officer Perez mistakes Cordell for a suspect. Trey offers to help Liam with a project. Meanwhile, Colton is struggling with his feelings for Stella.