The ZBZ women attend their national sorority convention; a party for the engineering department gets out of control; Evan takes advantage of Frannie’s absence.

Kramer returns to work after his 12-year strike is settled; Jerry dates a woman whose appearance fluctuates; George gives holiday gifts in his co-workers’ names to a fraudulent charity.

Three new murders related to three unsolved (or incorrectly solved) crimes from the past come back to haunt the CSIs.