Elton John, Lady Gaga enthrall fans at surprise concertWashington D C, Feb 28(AZINS) For their fans, it was a delight to watch Elton John and Lady Gaga performing together at a legendary music site in West Hollywood.

The 29-year-old singer, who sported a midnight blue buttoned military-style mini dress, sky-high platform lace-up boots and shoulder-length platinum blond hair, joined John for a duet Don't Let the Sun Go Down on Me at his surprise concert, E! Online reports.

While performing, the Judas hit-maker took on George Michael's former role, with John, who sported a black and red embroidered jacket and red shirt on the occasion. The singers shut down several blocks of the Sunset Strip for the hour-long show.

Other who attended the concert, that was live streamed on AOL, was Gaga's fiance, Taylor Kinney. Interestingly, the Sacrifice hit-maker and the Poker Face songstress, who are longtime friends, earlier had teamed up for the duet Hello for the 2011 animated movie Gnomeo & Juliet.