A 12 year old girl goes to school with drugs.

Before Magda's wedding a hair bandit must be caught.

Jinny's Dad is hospitalized which brings the family together. Magda and Gabe are desperate to find a bone marrow donor for Ben as he is not responding to the treatments. Kate gets an offer from Louis that is too hard to pass up, and C.D. and Nate close in on the white supremacist killer terrorizing San Francisco.

CD and Nate find out if a woman was raped by her best friend's boy Friend; Kate wonders if her relationship with Louis will continue.

Kate finds herself in hot water after her friend tells her that she somkes Marijuana.

Kate is in the hospital & can't feel her arm she doesn't want anyone to know she is ill in hopes of being Chief Of Police. Kate wonders if being Chief of Police is possible. Magda starts to hope Jinny will get help, CD & Nate want answers as to why Mia (the lady online) who may have fallen in love with Thomas Clark.

Jinny sees a therapist and finds she will need pills and worries about being hocked again, Kate will need surgery to remove an artery. Kate is alone and wonders if things will go well.

Jinny learns that Jack will move, the team watches a crime about to happen. Kate begins her recovery. Magda tells Jonah she might be having a baby, Jonah isn't ready for kids.

Kate comes home from the hospital CD & Nate try to catch prisoners who escape custody hurting Nate. Jinnny & Magda talk about if she will have a baby while waiting for Gina Bracken. None of the team likes the new captain because he wants everything done by the book.

Gabe is disappointed that she isn't pregnant. Kate asks to be updated on things, she can't get used to having a stroke.

Jinny leans that the gun that was used to kill a Marshal also killed her brother John.

Jinny vows to avenge her brother's murder. Kate pays a visit to The Division and has mixed feelings about a new boss taking over. CD tells Nate her fears of almost losing him after he nearly got shot. CD & Nate go to a bar to meet a suspect but end up in a shootout. Raina thinks about dating Johnny. Magda ends her affair with Jonah. Jinny into Ray the man who killed her brother. Kate thinks about leaving her job until she finds out that the new boss is planning to fire Jinny. In a season-ending cliffhanger, one of The Division is shot.

Jinny & Magda are trying to find burglar Grant coal train but they must deal with a bounty hunter who is also looking for the burglar. The methods used by the bounty hunter drive Jinny & Magda crazy.

Kate fights to keep her Granddaughter from the surrogate mom that wants to adopt her.

Nate and Raina look into the Suicide of Tom Burke who worked at the same facility that Irene (Nate's sister lives. Irene believes Tom was murdered. While Nate questions Bob about Tom Burke and weather Tom took his medicine they find out Bob did not't give out medication.

Raina & Nate wonder how Tom got his medicine.

Kate, Raina, Nate, Magda, and Jinny must find a way to get Stacy, the principal, and 10 students out of the school safe and sound when they're held hostage by armed terrorists. The team meanwhile must figure out who these people are and why they're doing this. Also, Jinny and Hank get married.