Holmes takes an immediate interest in the case as the unusual method of killing is that of "The Hoxton Creeper" (Rondo Hatton), known to be Conover's right-hand man.

Conover, when pursued by the police, had fled through the workshop where they were being made, and hid the pearl inside one of six identical busts.

Conover and The Creeper arrive at the house of the owner of the final bust, only to find that Holmes has taken his place.

[3] Universal Studios attempted to capitalise on Rondo Hatton's effective portrayal of the Hoxton Creeper, casting him in two more (unrelated) films as "the Creeper": House of Horrors (filmed in 1945, but not released until 1946, after Hatton's death) and The Brute Man (1946, also released posthumously).

[2] A character called "The Golem," a direct reference to the Creeper, appears in the third episode of the first series of Sherlock.