Goofs

When Slade is unrolling Kitty's invite/handbill the first time, the rear is blank. When he reads it the second time, the content of handbill can be seen through the paper.

A leading performer like Kitty would have a dresser to assist her in donning and doffing her costumes. She would not be in her dressing room by herself.

This is an example of "artistic license" and, as such, is not a Goof. Per IMDb Guidelines for "Factual errors", "We make big allowances for artistic license and suspension of disbelief - you might not be able to do that "in real life", but that's why we love watching movies."

The hand of the first victim moves.

At the end, when Slade's body floats by, some air bubbles surface giving the impression that Slade farts.

The police inspector says that a fingerprint was taken from one of the Ripper murder scenes, and the inspector himself carries a vial of fingerprinting powder. However, the Ripper murders took place in 1888; the first criminal identification from fingerprints took place in Argentina in 1892, and the British police did not adopt fingerprinting until 1901.

The police use flashlights which would not be invented for another ten years.

Inspector Warwick says that handguns are illegal in England "even for the police". At the end, he is chasing Mr. Slade with, and firing, a handgun.

In the Black Museum, Inspector Warwick mentions the "four murders", but at this point there had been five killings.