CSI Crime Scene Investigation

The CSI team, with the help of local tipsters, fights to save a neighborhood on the brink of being taken over by a violent street gang.

The CSIs question a young man who is found covered in blood in the street. The man believes he has murdered someone, but has no memory of who he is or who he might have killed. Is his amnesia genuine, or does he know more than he claims?

While investigating an elderly woman's murder, Grissom receives a miniature crime scene replica; Greg attends a hearing to ascertain his culpability in a teenager's accidental death.