The BAU team face one of their toughest cases yet ,when a prolific, border-crossing serial killer leads them on a hunt into Canada.
Sue comes up with a new cheerleading stunt, and Schuester and Beiste force the football team and the male Glee Club members to work together.
Earl decides to quit smoking and soon discovers it's harder than he anticipated; Joey comes to a conclusion on the best way to inherit Earl's money.
An FBI agent once romantically involved with Stillman asks the team for help finding a serial killer who has evaded her for 30 years.