So Holmes watches the tapes at the brownstone. Wade does sound smug as he offers to watch the crime scene again and again. Watson comes home and Holmes says he left urine in her room. "Tell me it's in a cup," she sighs. In her room, she takes out the sheaf of letters.
Carrie (Gregson's old partner) talks to the camera about how she's interrogating Wade Crewes. Gregson brings him a black coffee. Holmes runs upstairs and says he needs Watson because this is something bigger than the two of them. And also because it has a moral component, which is something she's better at.
Holmes says that the first interrogation had a paper cup, but that the second had a mug. And it looks like the one at the crime scene. Watson agrees that it's the same one. Holmes: "The evidence was planted. And it was Captain Gregson who gave him that mug."
Holmes interrupts Gregson while he's pouring coffee. He asks why he asked him to watch the tape. Obviously Holmes was going to notice. Gregson takes off his coat as Holmes talks to him about how he's sure any framing was done out of frustration. Gregson does a good job of not talking while Holmes babbles. He says he never planted evidence. Holmes asks how the mug showed up at the crime scene, and Gregson violently opens the door for Holmes to get the hell out of his office.
Holmes comes downstairs at the brownstone, unsatisfied. Watson offers him the letters and he takes them stiffly. She says she didn't read them: "Whatever happened, this is not how I want to find out about it." And she says she won't ask him about them anymore. Holmes thanks her (slightly less stiffly), then puts the letters in the blender. He explains that he left them at the rehab facility because he didn't want them anymore.
Holmes has restarted the old Crewes investigation. One early suspect, Victor Nardan, has been in jail for twelve years, then came out three weeks ago. The police have lost track of him, but the jail photos show that he has tattoos for Chechnya's premier football club. Holmes concludes, "Wherever he is, he will want to watch his beloved team." There are only three bars in New York that show Chechen football and they're all within walking distance of a specific hotel. No Victor Nardan, but there's a Victor Jones, which is his official alias.