It's anti-bullying week at 'Sesame Street' and everyone's favorite Muppets are speaking to the importance of treating everyone with kindness and respect.

To commemorate the occasion, rock legend Elvis Costello stopped by the Street to share the story of the time a mean old monster came along and kept him from counting to 10. 

Elvis was joined by Elmo (wearing a classic Costello getup, natch) for his performance of 'Monster Went and Ate My Red 2,' which will be familiar to longtime fans as a reworking of his classic track '(The Angels Wanna Wear My) Red Shoes.' Of course, instead of romantic longing, Elvis is singing about the heartbreak of watching Cookie Monster eat his red number two -- and unlike the original track, 'Red 2' has a happy ending.

A long list of pop stars who have stopped by 'Sesame Street,' including Stevie Wonder, Johnny Cash, Tony Bennett and Alicia Keys, but Elvis and Elmo's duet might be our new favorite.

Watch the clip below: