A car crash results in the death of a photographer; Maggie sympathizes with his widow when she notices similarities with her own husband's death.

After an altercation with a student, a teacher goes missing, leading the team to investigate everyone who might have had a grudge against him. Also, a key witness in the case steps up to help, and Maggie does whatever she can to ensure their safety.

A former kidnapping victim is linked to a series of murders that includes the daughter of an NYPD detective. Also, Kristen begins to doubt her ability as an agent after a training exercise leaves her shaken.

Five-0 must find McGarrett and Alicia when they are kidnapped by the serial killer they’ve been hunting,

After learning the school fire wasn't an accident, Chief Boden turns up the pressure on Severide and Casey to investigate the cause of the fire that trapped his wife. Fueled by a competitive bet against Firehouse 87, Mouch pushes all of the wrong buttons in his need to win the competitive challenge known as the firefighter muster. Meanwhile, as Kidd settles into her new living arrangement, her unresolved feelings prompt her to question the intentions of newcomer Hope.

When JJ arrives home shaken after a rough case, she breaks down and tells her husband about the abduction of two children.

The BAU welcomes back Emily Prentiss as they are called upon to investigate the disappearance of three women

As Joel fights to survive, Ellie’s struggle to save him stirs memories of her life in a FEDRA orphanage. Weeks before meeting Joel, Ellie recalls joining her best friend Riley for a night to remember… one that will change the course of both of their lives – and the fate of the world – forever.

The Titans race against time to save Sebastian before the Blood Moon ritual, while Conner’s new hardened personality rears, and Gar is presented with an ominous choice.