Metallica and Lang Lang, "One" (2014)
Metallica have always prized the virtuoso chops, complex compositions, instrumental force and high seriousness of classical music. So this collaboration with the most renowned Chinese concert pianist of his age made some sense – at least in theory. Lang Lang performed a dramatic solo prelude as flames shot up behind him, and then the ominous guitar introduction to "One" upstages him and his playing slips into the ensemble. When he competes with the guitars during the song's solo sections, he can't match their volume and his playing grows harsh and discordant to compensate – certainly a more avant-garde moment than the Grammys usually offer. Lang would be back the following year in a more conventional setting, performing "Happy" with Pharrell and Hans Zimmer.