When a family of four is abducted while on vacation in Barbados, the BAU is called to assist Unit Chief Jack Garrett and his International Unit on their investigation. Garrett and his unit, the FBI's top division for handling cases involving Americans abroad, work jointly with Hotch and his team when they discover that this case matches one the BAU investigated last year in Florida.

When three people implicated in murders claim they were attacked by a "clawed shadow monster" at the moment each crime occurred, the BAU searches for an UnSub who is controlling their minds. Also, the search for the culprit puts one of the team in jeopardy.