Greg and his friends, bored, decide to explore the old Coffman house. It's been abandoned for as long as they remember, in general disrepair, and a weird looking homeless man they call Spidey hangs out there.
In the basement, Greg discovers a camera hidden behind a secret panel. Though he knows he shouldn't, he takes it. When he takes a picture of his friend, Michael, the developed photo shows Michael falling through the air. Moments after the photo is taken, the railing Michael had been leaning against breaks, and he falls to the basement floor. Can the camera take pictures of the future?
The fourth book in R. L. Stine's Goosebumps series, Say Cheese and Die! is a little different from the first three. Rather than focusing on a pair of protagonists, Say Cheese and Die! has a group of four: Greg, Michael, Doug (who they call Bird), and Shari.
The camera shows horrible futures in each picture it takes: Greg's father's new station wagon, totalled; Bird, lying on the baseball field, unconscious and hurt; and Shari--vanished!
Each of these things come true. Greg's father is hurt badly in a car wreck, Bird is hit in the head by a baseball, and Shari disappears from her birthday party, without a trace. The police are unable to find any clues to what happened to her. Angry and frightened, Greg tears up the photos he took of Shari, photos which just show a tree in an empty yard.
Two hours later, Shari calls him. She tells him that she appeared in front of her house, about two hours ago. The last thing she remembered was being at her birthday party.
Could the camera be actually causing these evil things to happen? Greg is determined to return the camera to where he found it, and he and Shari go back to the Coffman house to do so. When they've done it, they're confronted by Spidey, who tells them that his real name is Dr. Fritz Fredericks. His lab partner had invented the camera, and he, out of greed, stole it. His lab partner, though, was an expert at the dark arts, and cursed the camera, so that he couldn't profit from it. Because of the camera, he lost everything, and he resolved to keep the camera safe and hidden, so he'd put it in the Coffman house.
Greg and Shari know too much, now, and Dr. Fredericks will not let them leave. There's a struggle, and his picture is taken by the camera, shocking him into letting them escape. When he doesn't seem to be chasing them, Greg and Shari double back to see what happened. They find him, as the photograph shows, dead--frightened to death by what the picture might show.
They put the camera back, then return home and call the police, who determine that Dr. Fredericks died of heart failure. Only Greg and Shari know what really happened. Unbeknownst to them, however, two bullies, Joey Ferris and Mickey Ward, saw them hide the camera. They retrieve it, take a picture, and wait to see what develops...
In terms of story, I think that Say Cheese and Die! is the best Goosebumps book so far. The characters are a little flat, but the camera and the trouble it causes were interesting enough to keep that from detracting from my enjoyment of the book. It's definitely worth a read.