A man wearing a jacket full of explosives goes to the cashier of the Eclipse casino and blows-up, killing three people and injuring several around him. In Los Angeles, Catherine Willows tells her director that she owns the casino and will travel to Las Vegas. Russell assigns his team under the command of Sara to process the casino. Catherine meets Jim Brass, who works at the Eclipse now, and the employee Romina Gonzalez, who dies before reaching the ambulance. Then she asks Sara to work in the case, despite the conflict of interest. The wife of the bomber, Aisha Karmimi, tells Sara that her husband was not a terrorist and had only gambling problem. He was under therapy and got worse when the therapist quit her job. Morgan processes the surveillance tape and notes that a metallic object flying from the bomber's jacket. The object has the letters" LHK" and Greg identifies as Lady Heather Kessler. Russell brings Gil Grissom to help him to find the whereabouts of Lady Heather. He is welcomed by Catherine's daughter Lindsey, but he does not recognize her. Grissom and Sara go to Heather's house and find blood and the furniture overturned. Soon the CSI's learn that Heather quit her therapist practice when her granddaughter died three months ago hit by a car. Catherine and Sara return to Heather's house and find bombs in her secret Red Room. Meanwhile, in a school, the audience is watching a school play when a woman wired with explosives walks to the stage, one parent sees the bombs and cries, and people leave the theater with their children. A technician from the bomb squad comes to help the woman but she triggers the explosives killing them two. The woman was a teacher from the school that was under therapy of Lady Heather. Sara and Brass return to Heather's house, and she finds that the tapes with the last three months of session are missing. Out of the blue, a woman runs to Heather's car that explodes, injuring Brass. Grissom brings Lady Heather to the station, and she tells the CSIs that someone is framing her. But who and why?
"CSI: Immortality" is the finale of "CSI" that most of the fans were expecting to see, showing the fate of the characters. Russell is moving to east to another challenge. Sara will be the new Laboratory Director, replacing Russell and working direct under the command of Sheriff Ecklie. Finn is gone, killed by the Gig Habor Killer. Nick now is in San Diego as the Laboratory Director. Catherine is thinking about returning to Las Vegas, since Lindsey is working in the laboratory. Grissom and Lady Heather return and he opens his heart to Lady Heather, saying that he loves Sara, and she helped him. Dr. Robbins, David Phillips, Greg, Morgan, Hodges and Henry will stay in the laboratory. Last but not the least, Brass now works in the security of the Eclipse casino. Therefore, a nice conclusion for a fifteen-year show. My vote is eight.
Title (Brazil): "C. S. I.: Investigação Criminal - O Filme" ("C. S. I.: Criminal Investigation - The Movie")