Penn was a star director on Broadway, winning Tonys for All the Way Home and The Miracle Worker, which he later made into an Oscar-winning movie; he went on to score in Hollywood, forging a strong rapport with the demanding Warren Beatty as a star in Mickey One and star-producer of Bonnie and Clyde, which was Penn's crowning achievement.
Bonnie and Clyde holds up extraordinarily well: it feels fresh, smart and very indie. It's hard to imagine how bold and violent the film was at the time. Dede Allen's stacatto editing and the brutal action was too much for many moviegoers and critics. Pauline Kael was a champion who helped turn the tide in 1967, as did Roger Ebert. (Mark Harris's account of Bonnie and Clyde's production is in Pictures at a Revolution; Peter Biskind's is in his Beatty bio, Star.) Film clip below.
Penn also directed the lauded revisionist western Little Big Man, starring Dustin Hoffman. His other western, The Missouri Breaks, is a classic case of a movie--and out-of-control movie stars Marlon Brando and Jack Nicholson-- run amuck. Night Moves is a great 70s film noir, starring Gene Hackman in a breakout role.
I met Penn in 1987 when we both attended the Havana Film Festival (along with Bob Rafelson, Oliver Stone, Alex Cox and Sonny Mehta). He lent me a grey t-shirt when I was shivering in an unheated airport waiting room. He was a gentle, soft-spoken, thoughtful and articulate man, and it's a shame that Hollywood--as it tends to do--did not offer him more opportunities to share that filmic intelligence with the rest of the world.
Bonnie and Clyde clip: