Back at the lab, Warrick recognizes the unidentified white corpse. His name is Benny Harper, and he was a private investigator with a huge rap sheet.
With this new information, Gil (William Petersen) and Nick go to investigate Benny's office. The office, however, has been sanitized. They find a set of keys in the desk leading to a car parked outside, but even the car has been completely cleaned. The computer has also been wiped clean, but the intrepid Archie Johnson was able to retrieve everything that was on it.
Meanwhile, Warrick is out somewhere and disturbing things are happening to him, involving the vic, some dead girls and bright casino lights. After what appears to be a long time, Warrick calls Gil, distraught and unsure about what he did, and then a whole mess of cops arrest Warrick.
Gil makes his way over to the place where Warrick is arrested. Warrick is illuminated by green light, and a prominent Las Vegas gangster by the name of Lou Gedda is lying dead in a pool of blood next to him. Gil questions him, but Warrick doesn't know what happened. Brass and Gil advise him to say nothing and get himself a lawyer. They escort him out to the cruiser, Warrick's head bent in shame. Willows (Marg Helgenberger
) and Nick (George Eads
) show up to the scene, and they are all informed that the day shift will be processing the scene, not them. The CSI team is not allowed to investigate, but Gil asks the day shift for the raw data from Warrick's case.
In interrogation, Warrick says he doesn't remember much, but he does remember that he hired Benny Harper to investigate Lou Gedda. The next thing he knew, he woke up in a pool of blood. He admits, however, that the evidence suggests that he was the one who whacked Gedda.
Willows pays a visit to Warrick to check on him and provide some support. The interrogation isn't over yet, though. The cop asks him about Holly, the CSI who died because of Warrick. The cop is trying to connect that case with Joanna's death and also with the current one by claiming that he has a pattern of reckless, obsessive behavior. Finally, Warrick asks for a lawyer.
Everyone strikes out in their search for new evidence. Everyone, that is, except for Gil. He notices that the ligature marks on Gedda's wrists don't match Warrick's handcuffs. Gil and Willows believe that Gedda's and Harper's murders are linked, and they also remember that Brass suspected that Gedda might have had a mole in the police department who might have committed both murders. By analyzing fingerprints at all crime scenes and through process of elimination, they determine that the dirty cop is Daniel Pritchard. Pritchard is likely to only be a minion of the real brains behind the operation, but as Gil says, they can't win 'em all.
Gil gives Warrick the good news that the D.A. is dropping the charges against him, but because of the issue of administrative delinquency, Warrick will just be suspended and demoted, but not terminated. Warrick is a free man. The CSI team takes Warrick out to a greasy spoon to celebrate. After the meal, Warrick goes out to his car alone. Uh oh, this can't end well. His superior, the under sheriff, finds him in his car and tells him that he doesn't want to fire him, but he just has to make sure that his rogue cop days are over. Warrick can't promise anything because the bad guy he's looking for is still out there. Ooh, wrong answer. The old man is the bad guy! He pulls out his gun and shoots Warrick dead!