The hard-boiled detective is a staple of movies from the past up to the present day. The appeal is obvious, and similar to that of the samurai or the cowboy: The hard-boiled private dick is a guy who lives by his own moral code, without letting personal entanglements or selfish motivations take him away from his rigid moral path. Also, he tends to get shot at and beat up a lot, which makes for exciting movies. Here are seven of the most hard-boiled movie detectives.

Philip Marlowe


Probably the most famous of all the hard-boiled detectives, Raymond Chandler's famous hero is the only person in LA with any kind of moral code (if the books and movies are to be believed). He's been played by everyone from Humphrey Bogart in "The Big Sleep" to Dick Powell in "Murder, My Sweet" to Robert Mitchum in a series of Chandler adaptations in the 70s. And he's as hard-boiled as they come-mostly because he has to be in order to survive.

Sam Spade


Dashiell Hammett's private eye hero of his novel "The Maltese Falcon" was most famously played by Humphrey Bogart with the kind of hard-boiled edge that can't be duplicated in today's slick modern world. He stares down fearsome villains like Sydney Greenstreet without blinking, and ends up outsmarting everyone after the titular object (although he doesn't get a hold of the Falcon either).

Lew Harper


One of the big hits of Paul Newman's "star period," "Harper" features Newman as the somewhat old-school private eye Lew Harper in the swinging 60s technicolor LA of the year it was made. And he came back for a sequel in the 70s, the tragically underrated "The Drowning Pool," which not only improves on the somewhat dated original, but features one of the most exciting set-pieces of all time, featuring Newman and an innocent woman trapped in an abandoned shower room being filled with water. In true badass form, he manages to survive AND get the bad guy.

Tony Rome


Who better than Frank Sinatra to play a hard-boiled detective? He does just that in "Tony Rome," a solid 60s mystery in the "Harper" vein. Since this is Sinatra, he brings a kind of sexy cool to the role, and he seems to be having fun being a Bogart-style badass. But don't get the idea that Sinatra is sleepwalking through the role - he's committed to being as hard-boiled as he can.

Gay Perry


Val Kilmer in "Kiss Kiss Bang Bang" isn't your typical hard-boiled private eye. Maybe that's because he lives in the real world, where a private detective's work is usually boring and meaningless. But when he invites Harry Lockhart for an evening of detective lessons, things get real weird real fast, and the dead bodies begin to pile up just like in the movies. This is when Perry really gets to prove his hard-boiled credentials, taking out henchmen with a gun hidden near his balls in one memorable scene.

Guy Noir


Kevin Klein's character in "A Prairie Home Companion" is an obvious parody of characters like Phillip Marlowe and Sam Spade, but he must have something resembling a hard-boiled heart in order to stay in this business for so long. Plus he's the only one who keeps his cool during the hectic and dramatic production of the final episode of "A Prairie Home Companion," the popular radio variety show (except for Garrison Keillor, of course, but that guy's more hard-boiled than all of us).

John Rosow


Anyone who's seen Michael Shannon in movies like "Bug" or "Take Shelter" might think he's an unusual choice to play a wisecracking private detective, but that's exactly what he does in "The Missing Person." Hired to find trail a mysterious man and his young male companion, Rosow gets involved in a case that ends up much bigger (and more personal) than he would have imagined. But in true hard-boiled fashion, he takes it all with a joke and something resembling a smile.