In the book Save the Cat! The Last Book on Screenwriting You'll Ever Need, Blake Snyder categorizes movies into ten basic plots. In the sequel, Save The Cat! Goes to the Movies, he expands on these plots in great detail. Many he calls "primal," saying you could "pitch (the idea) to a caveman." Snyder knows his subject well, as he wrote both Blank Check and Stop! Or My Mom Will Shoot. Snyder's categories are as follows (rearranged somewhat):
Monster in the HouseOne simple rule here: Don't get eaten. The three basic ingredients are vital to the success of this tale. Without the monster, there's nothing threatening the characters. But without the house, there's no reason they couldn't just up and leave, letting others deal with the problem. Stick the characters in a room, a building, a small village; put them in a spaceship, or on an island, or in a quarantined city. Suddenly there's no place to run. According to Snyder, a sin is committed, "prompting the creation of a supernatural monster that comes like an avenging angel to kill those who have committed that sin and spare those who realize what that sin is. The rest is run and hide." He includes movies from Alien and Tremors to Jurassic Park, along with just about every horror movie out there. Some movies, such as Saw, have monsters that go after the "sin" of ignorance. The archetypal Monster in the House tale is the myth of the Minotaur: You're stuck in a maze with a half-man, half-bull guy trying to kill you. You might call this plot the... inverse?... of Booker's Overcoming the Monster tale, where the Hero leaves home, gathers weapons, and heads across the world to find and destroy the monster that's been terrorizing the countryside. In Monster in the House, the Hero can't leave home, has no chance to build his arsenal before the showdown, and either destroys the monster for his own sake or fails to destroy it at all.
Out of the BottleThis plot deals with wishes and curses. On the wish side, we have a hero who makes a wish that gets unexpectedly granted. Or, less directly, perhaps he needs some help and gets it from an unexpected source - Snyder points out The Mask as being another tale following this plot. Then we get a classic Wish Fulfillment tale, although of course there's going to be problems. On the curse side, we have the "comeuppance tales." Liar Liar and Groundhog Day both count. There "must be something redeemable" about the hero, because he's going to have to change his ways in order to survive. And, eventually, because he's finally worthy of it, the hero gets what he wanted all along (in Liar Liar, it's "the respect of his wife and son"). The three important ingredients are: A wish asked for by the hero or granted by another, and the clearly seen need to be delivered from the ordinary; the spell that sets up the situation, and which has "rules" that must be followed; and the lesson that is to be learned from the experience.
WhydunitSnyder points to Chinatown as "perhaps the best Whydunit ever made." It's a walk on the dark side of the city, and once we've unraveled the mystery, we discover "something unexpected... dark and often unattractive" about human nature. This sort of tale makes us take a long look at ourselves and the things we're capable of. The Whydunit isn't about the who so much as the why, and the secret that the detective seeks ultimately forces him to take a dark turn somewhere, breaking the rules, even his own, in order to get to the bottom of the mystery.
Golden FleeceHere's Snyder's version of The Quest, which he connects with the Road Movie, a series of seemingly unrelated encounters that cause Character Development for the hero. He may never reach the goal he set out for, but he does reach a different goal: self-discovery. Which explains why this sort of movie has always seemed a little disconnected. It's not supposed to be - externally. Snyder then lumps in "all heist movies" along with "any quest, mission, or treasure locked in a castle" plot. The essential ingredients are a road, which is the journey that must be made, and will provide signposts that indicate growth; the team or buddy the hero needs to guide him along the way, and who represents things the hero lacks, such as skill, experience, or attitude; and a prize to be won—going home, obtaining a treasure, securing a birthright, etc. Compare Booker's version of The Quest.
Rites of PassageHere, the hero undergoes "pain and torment" from a vague force that turns out to be, well, Life. The hero has to come to grips with the realization that everybody goes through stuff like this, and surrender to reality - accept that there are aspects of reality that he "cannot control or comprehend," yet continue onward with a level of peace about the whole affair. Any sort of "life transitions" story fits under here. Also compare Booker's Rags to Riches plot. the essential ingredients are a life problem that must be dealt with, a wrong way to attack the problem, usually a diversion from confronting the pain, and a solutin that involves acceptance of a hard truth, and the knoweldge that it's the hero who must change, not the world around him. For the sixth season of Buffy the Vampire Slayer, the enemy was said to be "Life" (as opposed to the trio or even Dark Willow). So that probably counts here, too.
InstitutionalizedThis is the tale of a group: the mental patients of One Flew Over The Cuckoo's Nest, the doctors of Mash, the Mafia family of The Godfather. The story details the pros and cons of "putting the group ahead of ourselves." It honors the group - yet exposes "the problems of losing one's identity to it." According to Snyder, there's always a "breakout character whose role is to expose the group goal as a fraud." But there is also, often, a newcomer to the group, through whose eyes (and questions) we come to understand the dynamics of the group. After all, we're usually dealing with a "crazy... even self-destructive" environment, and unless we understand what's normal and what's crazy, it'll be hard to figure out what's going on. The essential ingredients are a group, family, organization, business, etc; the story is about the choice between towing the company line or being a rebel; and finally, a sacrifice must be made, leading to one of three endings—join the system, destroy it, or commit some form of "suicide."
Buddy LoveThe theme of this story can be boiled down to "My life changed for having known someone else" There are three basic types, as outlined by Snyder:
Dude with a Problem
The Fool Triumphant
So... there you go. Ten movie plots, as proposed by Blake Snyder in Save the Cat! This summary is of one chapter in: Save the Cat! The Last Book on Screenwriting You'll Ever Need, by Blake Snyder. Michael Wiese Productions, 2005