Immortality (CSI: Crime Scene Investigation) Immortality (CSI: Crime Scene Investigation) "Immortality" is the two-hour series finale of "" aired on September 27, 2015 on CBS. When a suicide bomber detonates his vest on the floor of the Catherine Willows-owned Eclipse casino, the FBI special agent returns from Los Angeles to join the investigation. Gil Grissom, meanwhile, working to preserve sharks in international waters, is arrested for trespassing at the Port of San Diego, and D.B. Russell offers Sara Sidle the chance to supervise the local investigation into the bombing. Sidle, who is vying for the position of director of the Las Vegas Crime Lab, is
CSI: Crime City discover that Monica was receiving unwanted attention from both the hotel waiter, Blake who also moonlights in the hotel spa and Pierre, another hotel guest who had shared drinks and made an unwanted play for Monica on the night of her murder. Upon further investigation CSI discover that Blake seemed to be following Monica around even swapping shifts with a colleague at the spa so that he could 'give it his best shot' with Monica and Pierre who had checked out of the hotel in a hurry leaving behind his expensive but smashed watch at the scene of the crime.