The famed magician Lafayette insisted that the pass door -- the small door leading from the stalls into the wings -- be kept locked during his performances, lest intruders discover the secrets of his illusions. This stipulation cost him his life...
When fire broke out on the stage of Edinburgh's Empire Theatre, on May 9th 1911, Lafayette rushed to the pass door, having forgotten that he had had it locked. Before he could make his way to the other exit, the stage was a raging sea of flame. Overcome by fumes, he fell unconscious to the floor. His body was later found, charred beyond recognition.
Sources
Will Goldston, Sensational Tales of Mystery Men