The Haunted House Plan was a plan for a Haunted House in Rowley's house. It had a "Hall of Screams", a "Lake of Blood", a "Bottomless Pit", a "Rat Tunnel", a "Maze of 1,000 Skulls", a "Knife Alley", a "Hand Hall", an "Acid Lake", and a "Death Slide". This plan ultimately failed because Rowley and Greg spent too much time making the fliers. They had to cut the actual Haunted House into the Hall of Screams and the Lake of Blood. The Hall of Screams was just Greg and Rowley on a bed while someone crawled through it listening to them scream. The Lake of Blood was just a kiddie pool with half a bottle of ketchup in it.