| "The Bob Next Door" | |
|---|---|
| The Simpsons episode | |
 Promotional image for the episode featuring Bart, Sideshow Bob and Walt Warren, the Simpsons' new neighbor who Bart at first thinks is Sideshow Bob. | |
| Episode no. | Season 21 Episode 22 |
| Directed by | Nancy Kruse |
| Written by | John Frink |
| Production code | MABF11 |
| Original air date | May 16, 2010 |
| Guest appearance | |
| Kelsey Grammer as Sideshow Bob | |
| Episode features | |
| Chalkboard gag | "Batman is not 'nothing without his utility belt'" |
| Couch gag | Harold from Harold and the Purple Crayon draws the Simpsons' living room before the family arrives, then draws a can of beer for Homer at his request. |
"The Bob Next Door" is the twenty-second and penultimate episode of the twenty-first season of the American animated television series The Simpsons. It originally aired on the Fox network in the United States on May 16, 2010. In the episode, Bart Simpson becomes convinced that their new neighbor is Sideshow Bob in disguise, but after a trip to the Springfield Penitentiary they find a distressed Bob still incarcerated. Eventually, Bart discovers that Bob has surgically swapped faces with Walt, who was his cellmate at that time, and still plans to kill him, although he is ultimately defeated.
The episode was written by John Frink and directed by Nancy Kruse. The episode guest stars Kelsey Grammer as Sideshow Bob. The episode's plot is based on the film Face/Off.
"The Bob Next Door" received positive reviews from critics; most agreed that it was a funny and exciting return to form for Sideshow Bob after "The Italian Bob" and "Funeral for a Fiend".