A shocking event during an arrest leads the CSIs to a series of bizarre deaths, involving green blood, squirrels and some toxic tuna.
Lab technician Hodges convinces his colleagues that Grissom needs their help in cracking the miniature killer case, so they review each of the four murders.
Catherine leads the investigation when a mutilated female body is discovered tied to the undercarriage of a bus carrying prisoners from a women's jail.
Grissom and Greg investigate a drive-by shooting on a limo. And Catherine tries to establish what happened to a young woman who was thrown out of a car.