Before "Happy," before The Voice, there was N.E.R.D. Pharrell reminded folks of this during Sunday's episode of his Beats 1 show, OTHERtones. He played a song that N.E.R.D. originally recorded for 2002's In Search Of — so when he, Chad Hugo and Shay needed to do more idiosyncratic music to counterbalance their more pop-oriented work as the Neptunes. Funny enough, the song is titled "Locked Away," though Pharrell sings about a woman who is in denial over their chemistry, not the song's rarity status.

Listen to N.E.R.D.'s "Locked Away" over at Apple Music.