What goes on during a One Direction after-party?  Apparently, a lot of bad karaoke to classic '70s hits, if a video captured by a fan's cellphone can be believed.

In the video , shot in New York City the week that One Direction played Madison Square Garden, 1D's Harry Styles can be seen duetting with the band's pal Ed Sheeran on a karaoke version of "Don't Go Breaking My Heart," the 1976 #1 duet by Elton John and Kiki Dee .  Despite the fact that both Harry and Ed are professional singers, they sound utterly awful, except for one moment when Ed actually sings on key. 

In the background, Harry's girlfriend Taylor Swift and One Direction members Niall Horan and Louis Tomlinson can be see dancing to the racket.

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