The CSIs are called to a shoot-out at a gun store involving four people. Later, a separate murder is linked to the gunfight.
Hodges presents the 'lab rats' with a series of hypothetical murders in order to give them a chance to play CSI.
The apparent suicide of a freshman on a university campus brings Sara back in contact with an old nemesis.
Henry's surprise birthday celebration turns into a disaster when the gang discovers a dead body in a shut-down barbeque joint.