In most Monk episodes, the sanity of obsessive-compulsive detective Adrian Monk (Tony Shalhoub) is a matter of debate. This time, however, it is Monk's police colleague Lt. Disher (Jason Gray-Stanford) who is suspected of temporary insanity. While under sedation in a dentist's chair, Disher sees--or thinks he sees--dentist Dr. Bloom (Jon Favreau) commit a murder. Unfortunately, no one believes Disher's story, not even his superior Captain Stottlemeyer (Ted Levine), and as result the lieutenant quits the force in disgust. Determined to prove that he was not hallucinating under the influence of anesthesia, Disher asks Monk (Tony Shalhoub). Before the story has reached its conclusion, Monk has uncovered a complex scheme involving stolen bank certificates--and has left himself wide open (or is it "open wide"?) for a painful dental demise right out of Marathon Man. ~ Hal Erickson, Rovi