When officers John Cooper, Ben Sherman and Chickie Brown rescue a baby girl found alone crawling across the middle of an LA intersection, the hunt for her mother begins. Detectives Lydia Adams and Russell Clarke examine the scene looking for clues, and soon Lydia finds herself affected by the search and must deal with some past issues -- taking a personal interest in reuniting the baby with its mother. Meanwhile, officers Sammy Bryant and Nate Moretta are unable to find the financial resources to put a juvenile key witness in police protection after an attempt on her life and must now convince the DA to place her in a student police program. And back at the station, everyone gathers for a retirement party for Dewey.