As Nolan finds the stash of evidence that Armstrong was using to frame him, his house is surrounded by police officers. Using delaying tactics, he denies the police entry and calls Wesley to serve as his lawyer. This allows Nolan to hide the evidence and his lawyer to run delaying tactics with a judge as Lopez actually works against him. While the LAPD largely believes in Nolan's innocence, Armstrong's injuries and work with Serj gives him the benefit of the doubt.
Commander West's own investigation uncovers what Harper and Nolan discovers but he is furious with the fact they conducted their own off-book investigation. Nolan's willingness to cooperate pays dividends, though, as he is used as a mole to get at the Derian mob. Armstrong escapes the hospital, though, due to Smitty's incompetence and meets with the mob before Nolan's meeting. The mob executes Armstrong, though, and only luck allows Nolan to overcome them.
Nolan and Harper both receive letters of reprimand as a result of their actions. Lopez receives a promotion to detective but neglects to tell anyone of her pregnancy.
- Asshole Victim: Few tears will be shed for Armstrong after his murder of Erin and attempted murder(s) of Nolan.
- Copkiller Both Armstrong and Serj are these with Nolan targeted by both.
- The Dark Side Will Make You Forget: All previous hesitation to his dirty deeds is gone from Armstrong at the end.
- Dirty Cop: Armstrong fully goes over to the Dark Side and is willing to kill Nolan without reservation.
- Frame-Up: Armstrong has done excellent work to establish Nolan as The Mole.
- Hero Insurance: Averted. All of the crimes that Nolan committed along the way to proving his innocence do nothing to prevent him from receiving consequences for his actions.
- It Gets Easier: True to what Serj said earlier, Armstrong is positively eager to kill Nolan this time around, unlike his hesitation with Erin.
- The Mafiya: The Derian mob is an Armenian mob that follows many of these stereotypes.
- Off on a Technicality: Rosalind implies that Armstrong's corruption will lead to her conviction being overturned, Armstrong having been the lead on her case.
- "The Reason You Suck" Speech: Commander West gives Harper one of these for the fact that their investigation of Armstrong is why IA exists in the first place. He clearly hates it when cops refer to IA as "the rat squad."
- Rewarded as a Traitor Deserves: The Derian mob executes Armstrong due to the fact he's no longer useful to them as a Dirty Cop.
