After an accident where the driver was decapitated during a dangerous stunt, the evidence leads the CSI’s to believe it was more than an accident. While gathering the evidence, the CSI’s find they must go into the world of “sideshows.”

When terror suspect Sonya Barak is targeted by her own people for assassination, she goes on the run, and Horatio sets out to capture her, both to protect her and bring her to justice.