Lately, I've been thinking about genre clichés, a topic that occasionally bubbles up in my brain, usually bursting like an embolism when said occasion is a new story of my own. I usually hate the goddamn things, especially when they're used to insert a cheap-ass twist into a story that doesn't need it. Movies are the worst at this: think the dead guy who doesn't know he's dead in The Sixth Sense, or the long-lost brothers of Desperado. (Sorry. Spoilers. If you slept through the late nineties, that is. You didn't miss much.)
Unless I'm (dead) wrong, there are two main schools of thought regarding clichés in mystery and crime stories, either of which can be linked to two classic pulp writers: Lester Dent and S. S. Van Dyne. If you're a Dent devotee, clichés are meant to be played with, malleable literary tropes not to be merely tolerated, but celebrated. If you're a Van Dyne dude, clichés are some bullshit. (If you're Quentin Tarantino, they're both right.)
Any curious, amateur crime writer with a computer has come across Lester Dent's "Pulp Paper Master Fiction Plot," the closest thing to paint-by-numbers writing you'll find. Dent is most famous for his Doc Savage stories, but his greatest contribution to the literary canon may be this formula. (His word, not mine.) Much of it still works, right down to the Aristotlean reversals and strange murder methods. He even breaks pulp stories down by act structure, much like Syd Field would do decades later with his scriptwriting books. Clichés abound, but that's half the fun of reading a pulp story (and all the fun of writing one). Like a fucked-up Joseph Campbell, Dent teaches you everything you'd ever want to know about writing old-fashioned genre fiction... except what to avoid.
That's where mean, old Van Dyne comes in. If your primary approach to writing is knowing what not to write, Van Dyne's "Twenty Rules for Writing Detective Stories" is indispensable. A pulp fiction Obi-Wan with a dash of Emily Post, Van Dyne's piece is an early example of plot twists to avoid, the kind of thing that runs rampant on the Internet today. Better yet, Van Dyne explains why these clichés should be avoided. If you've ever wondered why your story about the sidekick who turns out to be the killer was rejected, read this piece.
Genre fiction has evolved considerably since these gentlemen were around to break it down. With post-modern science fiction and mystery stories making the bestseller lists, ten cent trash has become hardcover treasure. Call them clichés tropes or essential elements; if you're going to write, it's best to be familiar with them.
Now if you'll excuse me, I have a pit of scorpions to tend to. Heh heh heh...