True Romance (1993)
Stars Christian Slater, Patricia Arquette, and Dennis Hopper
Written by Quentin Tarantino and Roger Avary (uncredited)
Directed by Tony Scott
Features a hilarious comic turn by then-up-and-comer Brad Pitt. And Dennis Hopper's scene with Christopher Walken is his best ever (which is saying something).
BONUS! You can read the entire original script for the film here.