Private Investigator Philip Marlowe is hired by wealthy General Sternwood regarding a matter involving his youngest daughter Carmen. Before the complex case is over, Marlowe sees murder, blackmail, deception, and what might be love.
A falsely convicted man's wife, Catherine, and an alcoholic composer and pianist, Martin, team up in an attempt to clear her husband of the murder of a blonde singer, who is Martin's wife.
After three men are convicted of bank robberies, Charlie becomes suspicious. After some investigation Charlie finds the men are innocent and that the fingerprint evidence used to convict them had been forged. Charlie then proceeds to find the true bank robbers.
Boston Blackie, in the 11th film of the Columbia series, indulges in some wit-trading with a squirmy spiritualist who deals in blackmail, murder and the occult. "Blackie" out to help his pal, "Runt," recover some jewels, finds himself involved in the homicides, and also finds himself as the prime suspect, and now has to find the real culprit in order to clear himself. So "Blackie,", a man of many talents and already a proved magician from cases past, shows he knows a little bit about dancing skeletons, walking phantoms and spiritualism himself, and holds a séance to unmask the murderer.
An unsuccessful sculptor saves a madman named "The Creeper" from drowning. Seeing an opportunity for revenge, he tricks the psycho into murdering his critics.
Holmes and Watson board a passenger train bound from London to Edinburgh, to guard the Star of Rhodesia, an enormous diamond worth a fortune belonging to an elderly woman of wealth; but within the first hour of the trip, the woman's son is murdered and the diamond stolen and any of the passengers in their car could be the killer thief.
A famous scientist invents a humanoid robot (the titular "monster"), so a greedy rival scientist plans to steal it for use in his criminal plans. His henchmen often kidnap a trained gorilla (the titular "ape") from the zoo, to aid in the schemes.
Mortimer Brewster, a newspaper drama critic, playwright, and author known for his diatribes against marriage, suddenly falls in love and gets married; but when he makes a quick trip home to tell his two maiden aunts, he finds out his aunts' hobby - killing lonely old men and burying them in the cellar!