S14E6: The Great Louse Detective

In "Simpsonlar - S14E6: Episode 6," also known as "The Great Louse Detective," Homer gets a mysterious note warning someone wants him dead. To catch the would-be assassin, Chief Wiggum enlists the help of Sideshow Bob, who has plenty of experience in the murder department, albeit unsuccessfully. Sideshow Bob is given parole and moves in with the Simpsons to act as a consultant. After a series of misadventures and red herrings, Bob narrows down the suspects by attending a spa with Homer. A little spa relaxation is just what they need to figure out that Frank Grimes Jr., seeking revenge for his father's death, is behind the murder attempt. In the end, Frank Grimes Jr. makes his move during a parade float competition. But thanks to Bob's detective work and some last-minute heroics, the plot is foiled. Bob returns to prison, but not before showing a touch of humanity by saving Homer from being electrocuted—again. The episode wraps up with the Simpsons returning to their chaotic normality, no worse for wear.