Professor Samuel Lumber was a 19th century expert on the human mind.
While conducting a study on sleep patterns, Lumber created a a doorway which allowed him to enter the dreams of his patients. However, things did not go as planned and nightmares began escaping out of the doorway into his Harley Street office. Lumber was imprisoned in the world of dreams. The Paternoster Gang rescued him from the nightmares. To compensate them for their troubles, Lumber offered to give the gang lessons in sleep-improving meditation. (PROSE: The Dangerous Dilemma of the Dream Doorway)