Andres Saenz-Hudson

Gideon, Hotchner and their team head to Mexico to aid in the investigation of a serial killer who preys on the elderly.

In part two of a two-part episode, a member of the team is pronounced dead after being shot in the head. Not wanting to give up, Horatio has the CSI rushed to the hospital and watches as doctors try to bring him back. Meanwhile, the CSIs find evidence that could lead them to Clavo Cruz, the man behind the shooting.

A newly determined Talbot takes Coulson to meet the enemy and attempts to avert Earth's destruction.

When a student finds a former teacher's car keys in an old desk, Lilly and the team take a new look at the teacher's death, previously thought to be a fatal carjacking.

When one policeman kills another, the CSIs must determine if the shooting was premeditated or an accident.