Legendary musician Sir Elton John is set to appear as himself in an upcoming episode of the ABC country music drama Nashville. The "Bennie and the Jets" singer will perform alongside Sam Palladio's Gunnar in the May 18 episode of the series, which serves as the penultimate episode of season four. The 'Nashville' role is a rare scripted series appearance for Sir Elton, who most recently appeared on Lady Gaga's 2013 Christmas special, which also aired on ABC.