While apartment-hunting in Paris, sultry 20-year-old Jeanne (Schneider) meets Paul (Brando), a brooding, middle-aged American whose wife has recently committed suicide for reasons he cannot fathom. Within minutes, they make love in the empty flat, a desolate place that becomes their temple of carnality, but with strict rules established by Paul.

Scandalous in 1972 and still unsettling today, Bernardo Bertolucci's bizarre, fascinating psychodrama depicts sex not as a union of two human beings, but as a reflection of their alienation from each other. While the butter scene is justly famous, this isn't the only reason "Tango" stays with you. Just watch Brando closely here: at certain moments you catch a glimpse of that fiery young man in the ripped t-shirt, railing against the world's injustices, down but never out, and utterly, brilliantly alive. (Trivia note: reportedly, to build a feeling of spontaneity, Brando would improvise his own lines the day before shooting a scene. In many instances, Paul’s memories of childhood are Brando’s.)