Adrian Monk: First, we're gonna prove that you killed George Rowe to get his security pass.
Dennis Gammill: His security pass?
Adrian Monk: You needed it to get into the nursing home, in order to kill Miles Holling.
Dennis Gammill: Steve.
Mayor Steven Rudner: No, no, no. Care to tell me why?
Adrian Monk: Because of something you said, Mr. Mayor, five years ago. It was in Karen Stottlemeyer's movie, which which I thoroughly enjoyed, by the way.
Captain Stottlemeyer: Yeah. Me too. I watched the whole thing.
Adrian Monk: When you buried the capsule, you made a promise to Miles Holling. Remember? You said that if he lived another five years, that you'd dig it up again, so that he could add a final chapter to his autobiography.
Mayor Steven Rudner: That's right. I did.
Adrian Monk: If Miles turned 115, they would have dug it up. And in your paranoia, you couldn't risk that happening, could you? So you tried to scare the old man to death. Late night phone calls, death threats. When that didn't work, you realized you had no choice. You had to kill him. There's something in there. Something you thought no one would see for 100 years.
[flashback:]
Mayor Steven Rudner: I've written a letter to future generations, and I've asked my family and staff to do the same. Why don't we drop them in now?
[present:]
Adrian Monk: The mayor invited his family and staff members to add a personal note. Let's take a look at what Mr. Gammill wrote. Captain? Would you mind reading it?
Captain Stottlemeyer: "On December 2, 1998, I killed Darren Leveroni with my car. May God forgive me, because I will never forgive myself. Signed, Dennis Gammill." The urge to confess.
Adrian Monk: It's a cop's best friend.