Tells the story of a demented musician who haunts the Paris Opera House and plays a terrifying role in the career of a beautiful young singer

Ross Arthur, a boy who can always talk his way out of trouble--and who does not care whether he tells the truth or not--finds himself in an alternate world, the home of his double, where he risks punishment as an "Intruder."

After being put back to sleep and abandoned in an old museum, Slappy is brought to life by a curious girl on a school trip. Out for revenge, Slappy uses his powers to raise an army of creatures from the exhibits. But when the museum closes, Slappy and his new friends are locked inside with Arragatis, an ancient mummy with his own plan for revenge. It's dummy versus mummy as Slappy faces his most dangerous and frightening opponent yet! Can Slappy defeat...