Metallica will play their song "One" with Chinese concert pianist Lang Lang at this year's Grammys.

Guitarist Kirk Hammett told Rolling Stone that they are working hard for it and that:"It's gonna be completely insane."

Speaking from his home in San Francisco, Hammett continued: "Lang Lang has interjected himself into the song in a way I don't think anyone else has ever done in the course of our career. He's going to be playing major parts of the song. He's going to be playing through the melody."

'One' is a Grammy-Award winning song, the main highlight from Metallica's 1988 album '. . . And Justice for All'. At just under 8 minutes long, the antiwar anthem lyrics sung by frontman James Hetfield describe suffering after surviving a landmine.

Hammett says the band has already been working on a demo of the track with Lang Lang's contributions and it works. "He's going to be weaving in and out of my guitar solos, which is amazing for me, because I've never played with another instrument that's been able to do that so effortlessly."

The 56th Grammys will take place on January 26 in Los Angeles.

Watch Metallica's official video for 'One', and Lang Lang performing at the Royal Albert Hall below: