Unusual events ensue during Halloween, such as a murder of crows harassing a field trip; Maddie remains adamant she made the right call.

A murder weapon connected to a case from the 1990s suddenly returns, which prompts a series of flashbacks to 1989 that reveal Athena's first days with the LADP.

The first responders face a series of emergencies such as a warehouse robot gone rogue; Eddie's fight club becomes unruly; Hen confronts relationship woes.

An apartment building is damaged by a meteor shower and a hazardous waste truck crashes; Hen's guilt over the ambulance accident continues to weigh heavily.

The 118 deals with a series of incidents that happen during the holidays more times than others; Maddie tries to embrace the future by reflecting on her past.

A skydiving trip turns dangerous and an assistant's lunch goes awry; the family faces the pain of a challenging health decision that Michael must make.

A stunt meant to become a viral sensation goes awry; Athena examines a woman who fails to remember having a gunshot wound in her head.

An incident at a bowling alley and a problematic home renovation require the first responders' attention; Bobby and Michael go on a camping trip with Harry.

The team searches for a female suspect who uses her professional skills as a high class call girl to lure and kill high-powered executives.

The BAU team investigates a series of deaths with religious overtones, and Agent Prentiss learns she has a personal connection to one of the victims.

Hotchner relives his first BAU case when a recent slaying suggests that one of New England's most notorious killers has struck again after a 10-year hiatus.

The team tracks down an arsonist who is killing the residents of a small town by setting fire to the places where community meetings are being held.

The team heads to South Padre Island to track a pair of serial killers who are targeting college students on spring break; the suspects they find surprise them.

The team tries to hold a family together after they realize their son's disappearance may not have been the doing of the serial killer they apprehended.

A serial murderer sends the team a videotape detailing one of his crimes, and they soon discover a hidden message begging them to help stop his murderous ways