"Love Is Strange" by Mickey & Sylvia in Badlands

Absolute genius Terrence Malick's Badlands is largely an emotionally detached affair that is briefly interrupted by this lustful scene/soundtrack addition. He basically nailed Moonrise Kingdom's whole thing in 30 seconds, forty years beforehand. Love is indeed strange and boy are Martin Sheen's Kit and Sissy Spacek's Holly embodiments of just that.