The Penquin Pool Murder
Gwen Parker (Mae Clarke) meets her former boyfriend Philip Seymour (Donald Cook) at the local aquarium and asks him for some money so she can leave her husband, stockbroker Gerald Parker. However, Mr. Parker receives an anonymous telephone call tipping him off to the rendezvous. When he confronts the pair, Seymour knocks him out with a punch. As there are no witnesses to the altercation, he hides the unconscious man in the room behind an exhibit.
Schoolteacher Hildegarde Withers (Edna May Oliver) takes her class on a field trip to the aquarium. Shortly after tripping up fleeing pickpocket "Chicago" Lew (though he gets away), she loses her hatpin; one of her students finds it. Then Miss Withers sees Parker's now-dead body falling into a pool housing a penguin. Police Inspector Oscar Piper (James Gleason) arrives and uncovers several suspects: the widow and Seymour; Bertrand Hemingway (Clarence Wilson), the head of the aquarium, who had financial dealings with the deceased; Chicago Lew, found near the scene; and even Miss Withers herself, as it is later determined that her hatpin was driven through the man's right ear into the brain. Bystander and lawyer Barry Costello (Robert Armstrong) catches Gwen Parker when she faints, and acquires a client when she is taken in for questioning.
Seymour confesses to protect Mrs. Parker, but Miss Withers does not believe him. She convinces Piper to notify the press that the murder was committed with a thrust through the left ear.
Later, Costello passes along a message from Chicago Lew, in which he claims to know the identity of the killer. However, when Piper and Miss Withers go to see him at the jail, they find him dead from hanging. Costello concocts a way in which Seymour could have escaped from his nearby cell using a duplicate key (which is found), strangled Lew, and hanged him with wire without entering Lew's cell.
At the murder trial of Philip Seymour and Gwen Parker, while questioning Miss Withers, Costello slips up, showing that he knew that Gerald Parker was killed via the right ear. The motive is that he is Gwen Parker's current lover.
When Gwen Parker is released, the waiting Seymour slaps her in the face, to the amusement of Piper and Miss Withers. Piper then unexpectedly asks Miss Withers to marry him. She accepts. (However, in the sequel, Murder on the Blackboard, they are still single.)
mystery, murder, humor