Rob Sherman was a sports agent based in San Francisco.
Sherman saw his opportunity when he visited the courthouse, to answer a summons for driving with an expired license (his one and only criminal offense). While there, he crossed paths with petty crook Dewey Jordan, who must have mentioned that his prior convictions for burglary. Sherman pretended to be planning an insurance scam, needing a "burglar" to steal some items from his house, and offered Jordan the "job." After a second meeting to plan the details on the Bay City Pier, Jordan entered Sherman's home during the night, simulating a burglary.
But Sherman shot him to death, and, when Pam came running downstairs at the sound of the gunshot, shot her dead with a second gun, which he placed in Jordan's hand. He then called the police, having created a convincing story that his wife had been killed by a random intruder, whom Sherman then shot in self-defence.
However, there were several holes in his story that Adrian Monk noticed. But Sherman brazened it out, knowing that, without proof that Jordan was anything more than a stranger to him, he was safe. Inside, however, he was panicking, knowing that there was such proof: Julie Teeger and her boyfriend, Tim Sussman, had had their picture taken on the Pier and unwittingly captured Sherman and Jordan's meeting in the background.
Deciding that the best way to hide the photo from view was to disrupt the relationship between the two teens, Sherman had Clark pretend to be Julie's aunt, who hired high school football star Clay Bridges to woo Julie away. The plot almost worked, until Natalie Teeger and Monk caught Clay with his real girlfriend, and discovered the plot.
Rushing to the Pier to find and destroy the original copies of the photo, Sherman was pursued to the end of the pier by Monk, and succeeded in throwing them into the ocean. However, Tim, who worked on the pier, heroically dove into the bay and saved the photos. Sherman was arrested a short time later. (Monk: "Mr. Monk and the Birds and the Bees")