Posing as "The Spider", terror of the underworld, as well as Blinky McQuade, underworld habitue, Richard Wentworth (Warren Hull), celebrated criminologist, wages a desperate battle to foil the plans of The Octopus, whose outlaw gang is completly demoralizing the nation's transportation system. Wentworth's activities are quickly discovered by The Octopus, who is a member of the board of transportation businessmen who have requested Wentworth's help. The villain dispatches his minion of henchmen to kidnap Wentworth. The latter escapes , and disguised as Blinky hangs out at a hash-house dive known to be frequented by Octopus gang members, and learns that a passenger bus, loaded with explosives, is to be blown up. Disguised as The Spide and with the help of his faithful Sikh servant Ram Singh (Kenne Duncan), empties the bus terminal and drives the bus from the depot. The police, however, blame The Spider for the bombing. The wave of transportation terrorism continues and The Spider threads a dangerous course between the police and the Octopus. In his guise as Blinky McQuade, Wentworth finds a "dfeflection tube for specialized radios" in the safe of one oh the men he suspects of being the Octopus. A check of radio-tube suppliers reveals that equipment of this kind was recently installed in a technical school located in an office building. And significantly, the office building is located in an area from which messages from the Octopus to his henchmen have been traced. Arriving at the building, Wentworth finds a suspicious-looking sealed-off wing with no means of entry. Planting smoke bombs in the lobby, Wentworth waits until the fire engines arrive and he then uses a fire ladder to gain access to the sixth floor and, as the Spider, he leaps through an open window right into the secret headquarters of the Octopus. But the Octopus has a deadly surprise awaiting the Spider. Is this the end for the Spider and will the Octopus succeed in his goal of gaining domination of the country by gaining control of its transportation, communications , banking and utilities businesses?