Susan Murphy is stabbed to death while jogging in the park at night. Her baby, Brian ends up missing.
The investigation leads to her ex-husband Raymond and his girlfriend Caitlyn. Raymond drove out of town with Caitlyn's cell phone to try and give them both an alibi but gas station footage shows Caitlyn wasn't with him.
Caitlyn was jealous of Susan and the baby. She killed Susan and stashed the baby at a church, expecting it to be found. But a homeless woman took the baby and had been taking care of it. Jane and Korsak find the baby and he is given to Susan's sister after Raymond and Caitlyn are arrested.
Jane hasn't told Casey or her family about her pregnancy. Only Maura knows but Angela guesses that her daughter is pregnant and promises not to say anything until Jane is ready to tell her.
Detective Barry Frost is killed in a car accident on his way home from his mother's.