The cover illustration depicts Slappy the Dummy crawling out from under a bed, his eyes glowing red. The words "SLAPPY IS HERE" are scratched into the bed's footboard.
Richard Hsieh's life is about to become a total nightmare. His dad studies dreams and they hook his new Slappy doll up to the dream machine as a joke. All of a sudden, Richard's dreams are becoming scarier and scarier. Each time, seeing Slappy, his birthday present, come to life and wreak havoc. But they're only dreams, right? When his cousin Willow comes to spend a few days with him, she, too, begins to dream of Slappy. It's impossible! But when Slappy threatens to invade more kids' dreams, they’ll have to figure out how to defeat him before he becomes a dream master.
- This is the second book in the Living Dummy saga where the plot involves Slappy and dreams, the first being the Goosebumps Series 2000 book, Slappy's Nightmare.
- The concept of Slappy invading the dreams of kids is similar to the overall plot of the Nightmare on Elm Street film franchise.
- The plot is specifically similar to A Nightmare on Elm Street 3: Dream Warriors.
- The title might be also be a reference to the 1905 comic strip Little Nemo in Slumberland by Windsor McCay.
- The concept of Slappy going inside someone's dreams was previously featured in Download and Die! from the Goosebumps comic series.
- The main character, Richard Hsieh, is actually the name of the famous internet father of Tony Hsieh, Richard Hsieh. He is one of very few Goosebumps characters named after a famous person.
- Richard Hsieh is one of few Asian-American Goosebumps protagonists.
|Goosebumps SlappyWorld series|
|#01 Slappy Birthday to You||#07 It's Alive! It's Alive!||#13 Monster Blood Is Back|
|#02 Attack of the Jack||#08 The Dummy Meets the Mummy!||#14 Fifth-Grade Zombies|
|#03 I Am Slappy's Evil Twin||#09 Revenge of the Invisible Boy||#15 Judy and the Beast|
|#04 Please Do Not Feed the Weirdo||#10 Diary of a Dummy||#16 Slappy in Dreamland|
|#05 Escape from Shudder Mansion||#11 They Call Me the Night Howler!|
|#06 The Ghost of Slappy||#12 My Friend Slappy|