The cover shows Slappy the Dummy surrounded by a bunch of dummies in an attic.
In Night of the Living Dummy III, the main characters are Trina O'Dell and her brother, Dan. Their father, Danny O'Dell, collects dummies. One day, Mr. O'Dell brings Slappy home, after finding him in a dumpster. After repairing his broken shaft, he names him Smiley, unaware of the dummy's past. Trina finds a piece of paper in wrapped around Slappy's body and Slappy slaps her across the face. Naturally, nobody believes her. Trina and Dan's cousin, Zane, is coming for a visit. Their father makes them promise not to scare Zane, as had done so previously during a visit. After a while, a dummy called Rocky pops up in weird places, scaring Zane while Trina and Dan get the blame for each incident. Many things are ruined, like Zane's camera, the dinner table, and the film in Zane's camera by the 'dummy'.
Dan and Trina eventually catch Zane taking Rocky from the attic and it is revealed that Zane was trying to have some fun without them. The three make a truce not to prank each other like that next time afterwards. More catastrophes occur afterward, each with Rocky at the scene of the crime. Dan suspects Zane, and tell Trina, but nobody else believes them. To prove that Zane is guilty, Dan and Trina sneak up in the attic to wait for Zane to come up and steal Rocky.
To their horror, they discover Slappy trying to sneak off with Rocky, and Slappy tells them that they are his slaves. Dan and Trina try to dump Slappy in a well, but he comes back the next morning. Trina thinks back and remembers the words she read to bring Slappy to life. Trina thought it could put him to sleep too. Trina and Dan sneak up into the attic and read the magic words out loud. Slappy is still alive and well, but all of the other dummies come to life. They all huddle around Slappy, as he screams. It is then described that the dummies "pulled and tugged him", but Slappy is not killed. Afterwards, all the dummies fall down lifeless just as Zane walks into the attic. Zane spots Dan and Trina in the attic with the dummies lying around, and he rats them out to their father.
The next day, Zane leaves to go back home with his father. As payback for getting her and Dan grounded, Trina gives Zane, Slappy, as a parting gift. He wants to start learning ventriloquism. Also, Trina was asked to give him a dummy as a gift, and Trina gives him Slappy. Trina watches Zane get into the car, and sees the dummy winks at her..!
Cover Art Gallery
- This was the third and final book to feature Slappy in the original Goosebumps series. Slappy does not appear again until the second Goosebumps Series 2000 book, Bride of the Living Dummy.
- Night of the Living Dummy III has the shortest time difference sequels in the original series at 9 months.
- This is the second book in which the parents don't see Slappy in action or that the kids weren't lying.
- The title of both the book and television episode is a spoof of the classic 1968 horror film, Night of the Living Dead.
- This is the first book to have trading cards inside.