In the season premiere, a community parade turns deadly and family tensions and politics arise. A surprise visit from Lt. Col. Casey Jones (CHRIS VANCE) reveals shocking news.

Baby TJ's christening turns grim when a body is discovered in the church. Jane almost abuses her power in order to protect her brother Tommy (COLIN EGGLESFIELD).

Dr. Isles becomes the suspect in the murder of a mysterious guest of a charitable fund-raiser.

The decades-old death of a mother and child open a closet door revealing skeletons that threaten to complicate the start of Paddy Doyle's RICO trial.

A reclusive hoarder becomes the subject of an investigation into the murder of a city sanitation employee.

The hit-and-run murder of a high school science and driver's education teacher focuses on a group of friends who were also students of the victim.

"Sports rage" and angry hockey parents are the focus of the investigation of the murder at a youth hockey game.

When someone begins to stage copycat murders presented at a symposium on serial killers, detectives believe the suspect is one of the meeting participants.

The squad gets involved in an incredibly dangerous scenario when a horrifying incident occurs during a drag race; Jane gets a lead that points to drug trafficking being the motivation for a murder; an investigation is hindered.

A mock trial advisor (A'DA ALISON WOOLFOLK) dies during a competition. Meanwhile, Jane is concerned that Angela may be hiding financial issues. DOUG SAVANT also guest stars.

Two puzzling murders share a surprising link that could be the key to finding the perpetrators. Meanwhile, Jane and Casey come to a crossroad and Maura assumes caretaker for Patrick Doyle, Sr. who is being released from prison.

The Boston Police department is haunted from the past when a man in clown-costume almost kidnaps a little boy. Is it the same person that has molested and kidnapped boys in the 1980s?

A musician is stabbed in a bar and the squad realizes that the stabbing victim had something to hide. Jane's father returns with shocking news.