Det. Lopez is back in uniform to serve as Officer Jackson's training officer on his final day as a rookie. Jackson admits that she could have had him fired on his first day and thanks her for his career. Being a cop is all he's wanted to be since he was a child.
After Jackson shares how little he saw of his father when he was a boy and his dad was a detective, Lopez begins to worry about her and Wesley's child being raised by nannies.
Lucy believes she and Tim need to acknowledge the end of their relationship as she moves on from being his rookie. Tim says he doesn't think Lucy has what it takes to go undercover because she doesn't have the killer instinct to lie to someone's face, make them her best friend, and then stab them in the back.
Lucy responds by punking Tim, telling him she has genuine feelings for him and now that he's no longer her training officer, they can act on them. Tim is speechless until Lucy starts laughing. Later, Tim tells Lucy how proud he is of her and not to let anyone ever tell her she can't do something, not even him.
Prof. Ryan, Nolan's Ethics professor, comes for a ride-along with him and Harper. She also works in civil rights litigation and is writing a book. Harper and Nolan admit that cops are over-taxed by being asked to be cops, social workers, psychologists, teachers, etc. Most people don't understand that many cops want to see change too.
An Amber Alert comes across about a newborn baby girl taken from the hospital. Everyone assumes she was taken by her father, a known criminal with a drug problem, but when they find the father, he doesn't have her.
The baby was actually abducted by a woman, Rita, whose own baby died of SIDS that morning. When officers find Rita, she is standing on a bridge holding the baby, ready to jump. Nolan speaks to her, but then Lopez connects with her because she's pregnant. She gets Rita to look at the baby and realize it's not her own. Rita hands over the baby and goes with the officers.
It turns out that Prof. Ryan has already submitted her book for publication. Nolan and Harper are disappointed that she did that before actually seeing things from a police officer's perspective. Ryan seems to feel that she didn't need that to know that things need to change.
Nolan watches as Jackson and Lucy head out to celebrate the end of being a rookie. Harper sees Nolan's melancholy expression and orders him out to dinner with her and her daughter.