Shawn and Gus are at the SBPD waiting to pick up their check when they spot an attractive, ethereal woman named Nicole, telling the police that she witnessed a murder in an ally on a busy street at the height of lunch hour. Given the circumstances, Lassiter and Juliet are unsure whether or not she is telling the truth. Her story sounds unbelievable even to Shawn, but Gus is really attracted to Nicole and wants to further investigate.

As Gus confronts Shawn over the diamond ring he just discovered, a valuable shipment of artifacts is stolen from a museum, so Shawn calls in Pierre Despereaux to help them catch the thief who stole the shipment. It turns out to be an old dagger that she was really after. As usual, nothing is what it seems when Despereaux is involved, and they discover that the dagger is the key to a much bigger mystery.