Criminal Minds' Finale Promises a "Cannot Miss" Cliff-hanger

Criminal Minds by Karen Neal/ABC
In tonight's
Criminal Minds finale (9 pm/ET, CBS), the BAU team heads to New York City on the trail of a Son of Sam like serial killer - or is there more than one?
That's not the only question: J.J. (
A.J. Cook) makes a fateful pregnancy decision, Hotch (
Thomas Gibson) discovers he has an admirer and Morgan (
Shemar Moore) ponders leaving to run the New York office.
And in the explosive cliff-hanger, "one of our team is going to be severely injured, and [viewers will] have to wait all summer to find out who it was," says exec producer Ed Bernero. "If you care about these people, you cannot miss the last 30 seconds."