Officer Adam Kirk, an old friend of Stottlemeyer's, steps off a ferris wheel to find the young man he was riding with dead from a knife in his chest. Stottlemeyer has no choice but to arrest his friend and advise him to remain silent. He enlists Monk to investigate the case unofficially, even though Monk believes the hair-triggered cop is guilty. Matters are complicated when a criminal Kirk is charged with beating is released for lack of evidence, and more so when Monk discovers that the bruises on the victim's body were self-inflicted. Meanwhile, Stottlemeyer is forced by his conscience to state that Monk is not ready to rejoin the force and to endure the resentment of both Monk and Sharona as a result of this decision. When Monk, still furious with Stottlemeyer, figures out what really happened, he and Sharona return to the carnival and Sharona climbs aboard the ferris wheel to spot the escaping criminal because Monk is too afraid of heights to do it himself. But the criminal is hiding...