Adrian Monk: Door's open. Rhonda? Hello? It's Adrian, from group. [coughs]
Natalie: [coughs] Do you smell that?
Adrian Monk: Do I smell that? I'll be smelling that for the rest of my life. Rhonda.
Natalie: She's dead. She mixed bleach and ammonia?
Adrian Monk: Chlorine gas. Rhonda's worked here for nine years. She would never make mistake like that.
Natalie: Murder. Oh, my God, Mr. Monk, that's three.
Adrian Monk: Okay. Natalie, if I was gonna kill somebody, this is exactly how I would do it, with cleaning supplies.
Natalie: Look, Mr. Monk, it couldn't have been you. Relax. These aren't your brands. You buy the good stuff. These are the cheap store brands.
Adrian Monk: That's true. That's true. Danko.
Natalie: Who?
Adrian Monk: Xavier Danko. The other patient. We saw him at the supermarket, remember? He was buying cleaning supplies, the exact same bottles. Harold said that he quit group therapy about a month before Barbara O'Keeffe was murdered. Danko must have revealed something in therapy, something big, something worth killing for.