Alfons Carcasona

Frankie Bargher is hired by the government to pose as his own brother who became a target for two groups of evil agents.

Someone is killing people related to a South American expedition. The means of murder are poison darts with rubber spiders attached to them. A writer and some police detectives investigate.

Erik, the hypnotist Georg's assistant, is in love with Magda, Georg's fiancée, and secretly sends her roses every night. Chris, the guy delivering the flowers, who is also an amateur boxer down on his luck, takes advantage of the empty dressing room to steal the trio's bankroll, but he is caught by Georg, who is knocked out by Chris during a brief struggle.

An evil genius uses poison gas to avenge himself on his enemies.