Adrian Monk: Something's wrong. Did either of you move anything?
Natalie: No.
Kendra Frank: No.
Adrian Monk: Something's different. There was an envelope. A white envelope, right here.
Natalie: There was? Oh, it's a receipt. Registered mail, he mailed something to himself.
Kendra Frank: I remember that. That was about six months ago, I went to the Post Office with him. He was mailing sheet music to himself. He called it his insurance policy.
Natalie: What song?
Kendra Frank: I don't know.
Adrian Monk: I think I do. The song Kris Kedder was just singing.
Kendra Frank: Peggy's Gone to Memphis.
Adrian Monk: Kedder didn't write that song. Stork wrote it about his daughter. Peggy is short for Margaret. Peggy's Gone to Memphis.
Kendra Frank: Oh, my God, he just took that envelope.
Adrian Monk: We can't prove anything without that envelope.