CSI: Immortality

When a bomber strikes in a hotel, the team investigates. Catherine returns because the casino is her family's. Evidence found at the scene leads them to suspect Lady Heather, and when she can't be found, Grissom is asked to come to Vegas to help. He arrives and clearly things between him and Sara are a little tense. And everyone is sure Heather is involved, but Grissom doesn't think so. And when other bombings occur, they try to find out who is responsible.