The Nightmare Room was a series by R. L. Stine following the massive success of his Goosebumps series. It began in 2000, with its first book, Don't Forget Me! and was ended in 2001 with its last book, Visitors.
When R. L. Stine's Goosebumps series began to end, he planned a business deal with Harper Collin's Children to start two new book series, Goosebumps Gold, a spin-off of the popular Goosebumps series, and The Nightmare Room. Reports accounted that Harper Collin's was planning "an extensive marketing campaign" for Stine's work.
Goosebumps Gold, however, was cancelled for unknown reasons, possibly licencing, but The Nightmare Room began on September 30th, with the first book, Don't Forget Me! The series had a total run of 12 books, until it ended with book 12, Visitors, in 2001. A possible reason for the series' cancellation is the events of September 11.