When former BAU team member and current Interpol Agent Emily Prentiss tracks an international serial killer, she enlists the help of her friends at the BAU after she is convinced the UnSub's next victim is on American soil. Also, the BAU deals with Morgan's departure from the team.

The BAU enters into a dangerous game of cat-and-mouse with a convicted serial killer after guards at a Virginia prison intercept a package with evidence relating to the kidnapping of two boys several years ago. The team believes the notorious killer may have information on the boys' whereabouts.