In the midst of a heatwave and a citywide blackout, Officer John Nolan and Aaron follow increasingly large leads after they discover criminals hiding at the station. While on duty, Officer Chen makes an alarming discovery after being called to a scene where a pungent smell has wreaked havoc. Meanwhile, Lucy and Harper scheme to get Tim out of his new job and into a more exciting position.

Officer John Nolan and Bailey are on the hunt for a mystery gunman after a shooting hits a little too close to home. Meanwhile, Aaron struggles to live within his means and joins Lucy to help Tamara when the mother of a child she babysits goes missing. Elsewhere, Wesley suspects that a judge is taking bribes after he excludes valuable eyewitness testimony from a case.