The BAU is called to Wisconsin in search of a serial killer, and the team looks for a connection among the victims for clues to the UnSub.
Jack tries to influence a congressional election to help a candidate (John Slattery) for the benefit of the network; Jenna helps Liz find the perfect pair of jeans.
The team investigates when a Massive Dynamic employee (Ptolemy Slocum) is so certain he is being attacked by butterflies that he leaps from a window to escape them.
As the storm rages, patients are brought to the hospital by the busload and resources dwindle; a doctor's life hangs in the balance.
