A hunt for a murderer reaches its conclusion on 'CSI' (Thu., 9PM ET on CBS). But chasing a killer can mean death.

[Spoiler alert.]

All season long, Ray Langston (Laurence Fishburne) has been chasing a serial killer known only as "Dr. Jekyll." Now, in desperation, he seeks assistance from another bad guy -- Nate Haskell, also known as "The Dick and Jane Killer" (played by Bill Irwin). But when you ask for help from a psychotic, you need to remember to watch your back.

This is a lesson that Ray fails to remember. While talking to Nate in his jail cell, Ray literally gets stabbed in the back. Nate grabs him and attacks him with a shiv, wounding him over and over and over again. At the end, Ray lies bleeding on the ground. Will he survive? We'll have to wait until the fall to find out.