Must-listen: Lana Del Rey and Bleachers duet on 'Margaret'.

"This is a simple song, gonna write it for a friend / My shirt is inside out, I'm messy with the pen," opens Lana Del Rey in 'Margaret', writing about Jack Antonoff and his fiancé, Margaret Qualley.

"He met Margaret on a rooftop, she was wearin' white / And he was like, 'I might be in trouble' / He had flashes of the good life, he was like / 'Should I jump off this building now or do it on the double?'"

'Margaret' features on Lana's new album, 'Did you know that there's a tunnel under Ocean Blvd'.

Listen to 'Margaret' below...