When the kill count of a mass-murdering arsonist active in a small town reaches 31, the BAU are called in.
Midge hits the stage for a foreign audience, Abe and Rose are exposed to a new world, and Susie feels the consequences of having a bad reputation.
Devon pushes Bell to take drastic measures when a mother's complaints go unaddressed after her delivery; Conrad tells Nic about Jessie's worsening condition; a mother and son appear with devastating injuries.
A Navy lieutenant commander working on foreign cyber threats with the NSA disappears; the team gathers to celebrate the holidays.
The team investigate when a creepy mannequin prop inside a popular haunted house turns out to be a real dead body; Catherine enlists the help of Folsom to search for her friend who disappeared.