Swamp of the Hideous Zombies — Geoffrey Hayes

Illustrated in black-and-white. When a creepy fortune-teller moves into Boogle Bay, spooky things start happening. One by one, people disappear, and those who remain begin acting very oddly. Otto is convinced that zombie monsters are up to some sneaky tricks--he even spotted one skulking by the movie theater! Will the swamp zombies take over the town before Otto, his Cousin Olivia, and their Uncle Tooth solve the mystery and save everyone?