After a bachlorette party ends in murder, the NYPD evidence team must put the pieces together. Det. Stella Bonasera (Melina Kanakaredes) heads the group, and uses everybody else to help process. When Det. Lindsay Monroe (Anna Belknap) mentions the killer might be John McEnroe, the tennis player, Det. Danny Messer (Carmine Giovinazzo) is reluctant to agree.
The dead man provides plenty of clues, but Dr. Peyton Driscoll (Claire Forlani) cannot pinpoint a cause of death without further examination. Stella remembers the bartender saying a fight broke out between McEnroe and the victim in the bathroom, where he discovered the body. Although an arrest cannot yet be made, she and Danny find the sports personality chatting to autograph seekers. He denies guilt, but they take his DNA and fingerprints just in case.
A curious clue pops up when the cops discover a website where celebrity sightings are posted. After their prime suspect pops up online, Danny calls McEnroe's agent and confirms the man was at home with his family. Dr. Sheldon Hawkes (Hill Harper) breaks the case wide open with blood evidence.
It turns out the real killer is a man who could be McEnroe's twin if someone wasn't looking too closely. He ran into the bachelorette's fiance in the bathroom. A misunderstanding led to the altercation ending in murder.
Det. Mac Taylor (Gary Sinise) has an internal police investigation, his own, to work through. After he walks out of court, Det. Don Flack (Eddie Cahill) says he is not helping matters. Mac knows his work is not the problem, but himself. Chief Sinclair (Mykelti Williamson, Forrest Gump) is under both public and media pressure to address proper police procedure. If the chief hopes to become commissioner one day, getting Mac out of the picture makes sense.
The trial centers on the death of a serial killer, who would still be in prison if Mac had not put a dirty cop behind bars ("Consequences"). Det. Dean Truby was going to testify, but now is the one in the slammer. As team members are questioned on the stand, Mac is not portrayed in a flattering light. Danny, in particular, later wonders why Mac ignored policy and went after a killer alone ("Past Imperfect").
It's not long before Truby sends Mac a note, requesting a meeting. They sit down together, and Truby says he cannot blame Mac for his troubles. However, he also has a bombshell to share. Evidence is being stored which could send heads at the precinct reeling. Mac picks it up and finds proof of a potential coverup. He goes to the chief and Det. Stan Gerrard, and spells out his terms. While nothing is of a criminal nature, Mac could still go to the press. The next edition of the paper announces Mac's name has been cleared.
The internal investigation has played out for three episodes, which in my opinion is long enough. Could Mac have been fired? Perhaps, although I have always thought it unlikely since Gary Sinise is the lead actor. The twist was interesting, but Mac's reaction was predictable. He knew better than to take Truby's words at face value, so the evidence would have to speak for itself. Both Mac and the chief know a trial is out of the question, but Gerrard could still retaliate.