Season 4

Season 4 Episode 26 – To Hell…And Back (2)

The BAU continues its search for a serial killer who has forced the team into Canada to catch him and has placed a team member's life in danger.

Season 4 Episode 25 – To Hell…And Back (1)

In one of its most difficult cases, the BAU is called to Detroit to help track down a serial killer who forces the team into Canada to catch him.

Season 4 Episode 24 – Amplification

The BAU responds quickly after a serial killer releases a new strain of a deadly virus that threatens the public, which puts a member of the team at risk.

Season 4 Episode 23 – Roadkill

Local authorities summon the assistance of the BAU after a series of homicides occur that appear to have been caused by a serial killer's car near Bend, Oregon.

Season 4 Episode 22 – The Big Wheel

When a serial killer sends a videotape of one of his crimes to the BAU, the team discovers a hidden message from the murderer begging for help in stopping the killing.

Season 4 Episode 21 – A Shade of Gray

During an investigation of a series of child abductions and murders, the BAU concludes there is a possibility that one of the kidnappings may not be the work of the serial killer who had been apprehended.

Season 4 Episode 20 – Conflicted

The BAU is called to Texas to investigate a serial killer who is targeting vacationing students on spring break on South Padre Island.

Season 4 Episode 19 – House on Fire

The BAU is summoned to Indiana by local authorities when a serial arsonist threatens the residents of a small town by setting fire to community meeting places that kills several people.

Season 4 Episode 18 – Omnivore

The BAU travels to Boston when the serial killer from one of SSA Aaron Hotchner's first cases, which involved one of the most notorious murderers in the history of New England, returns after 10 years.

Season 4 Episode 17 – Demonology

The BAU is called to investigate a series of deaths involving exorcisms that appear to be sanctioned by the Vatican, and SSA Emily Prentiss finds herself personally involved in the case.