Lou Reed wrote the song for Nico after she approached him following a 1965 show and said, "Oh Lou, I'll be your mirror".
'I'll Be Your Mirror': The Story Of The Velvet Underground Classic
The track features a "small-scale" arrangement, highlighted by Moe Tucker's tambourine and a notable bass flub by John Cale in the intro. Warhol Film Footage
The film captures a 67-minute rehearsal at Warhol’s Factory . It features the band improvising and culminates in a visit from the NYPD following a noise complaint.