Gun Crazy is a 1950 film noir starring Peggy Cummins and John Dall and directed by Joseph H. Lewis. Ostensibly, it's about Dall's character, an ex-soldier who has had a long fascination with guns, and falls in love with Cummins' character, Annie Starr, who is a sharpshooter at a circus. What follows is, as the poster says: thrill crazy, kill crazy, gun crazy.
But you can forget the characters. Well, okay, you can't forget them, just as you can't forget the plot, but the true story is about violence and the violence inherent in humans. Dall's character, Bart, has had a fascination with guns since he was a kid - and not just guns, but shooting them. After all, that is what they are for. There is a darkness in him that only needs to smallest push from Annie to bring out.
Annie is an interesting study in violence, too. It's obvious that she's turned on by Bart's use of guns. This was back when the Hays Code didn't allow that much sexuality, but boy, do they hint at it. If there's anyplace where a gun really does represent a penis, it's here.
And, finally, there's the last scene. I really don't want to spoil it for anyone, but the last scene is masterpiece. It's dreamlike, it's dark, it's symbolic as fuck. But it's shows exactly what the entire movie is about: the madness in all of us, that fact that we are gun crazy.
Or maybe I'm reading too much into it.