Continuity mistake: When Mrs. Maxwell, the head of the "Occult Society", is arguing with her husband Milo, watch her dish of tapioca. In the first shot, a profile shot, the dish is full. When the shot switches to a head-on shot, the dish is nearly empty. In the next profile shot, the dish is once again full and she's just then taking her first bite.
Continuity mistake: After Luther slides down the coal chute and into the coal bin, his left arm is outstretched, but the next shot of Luther shows his left arm immediately beside him.
Continuity mistake: Outside the Simmons mansion, Luther and Mrs. Maxwell are standing by the gate. Closeup shot of Luther shows a bush behind him, being blown by a breeze. The shots of Luther and Mrs. Maxwell show Luther with the stone column of the gate behind him, not shrubbery, and no breeze blowing.