Stewart and Pattinson covered Elton John’s “Your Song,”" shares Marc Malkin of E! News, who broke the story of the karaoke singing stint of the Australia and Twilight cast and creative staff.

Straight from the horse’s mouth, so to speak, as Kristen Stewart narrated the events of the karaoke party in Tokyo Japan where she was a latecomer as Robert Pattinson was already carousing with his Australia buddies, whom he bonded with in the flight from Los Angeles to Tokyo Japan.

When [Kristen] Stewart first arrived at the bar, [Robert] Pattinson and [Hugh] Jackman were already engaged in a “really, really elaborate ABBA moment.” Later on, [Baz] Luhrmann joined Pattinson at the mic. “It was really funny seeing Baz Luhrmann and Rob singing a David Bowie song,” Stewart says. “It was a talky one so they both could sort of talk to each other, and they were riffing back and forth.”

She adds with a laugh, “They were looking longingly into each other’s eyes.”

It seems Kristen Stewart’s account partially matches a Just Jared Tokyo source.

A Tokyo journalist confirms to JustJared.com that the foursome, [namely, Rob, Hugh Jackman, Baz Luhrmann and producer of the 2009 Oscars opening number John Palermo] (plus friends) sang for a few hours before Rob’s costars Kristen and Taylor joined in on the fun. Photographers caught them leaving bar around 3AM.