A pitched rooftop battle between the Creeper and Sumo has ended with the latter man falling, seemingly, to his death. Sumo, however, lives. The Creeper is able to garner a bit of information from the badly injured Sumo, as his adversary loses consciousness. Switching back to Jack Ryder, the intrepid reporter enters a house in search of his associate, Rip Cord, and Sumo's companion, Bird. Cord is still suffering from the effects of a drug ingested in Proteus' laboratory. Bird, however, is on the move. Ryder tackles Bird, thwarting his attempt to flee. The two men struggle, with Ryder coming out on top. Before he can garner any useful information from Bird, Ryder is blackjacked from behind, and loses consciousness. Ryder awakens to find Cord largely recovered. Cord informs Ryder that Bird plans to leave the country, from the airstrip at Ainsley Filed. Ryder races to intercept Bird. At the airfield, Ryder transforms back into the Creeper, and runs Bird down. The two men struggle outside Bird's plane. Bird begins beating the Creeper with his briefcase, slowly pushing him back towards the plane's propeller blades. Inches away from a grisly death, the Creeper rallies all his strength, and puts Bird down. Walking over to a nearby pay phone to call the police, the Creeper is suddenly, violently thrown to the ground, when Bird's plane explodes.
At that moment, WHAM-TV's station manage, Bill Brane, and the weather girl, Vera Sweet, have arrived at Jack Ryder's apartment. Once inside, the two are taken at gunpoint by Ryder, who quickly reveals himself to be Proteus. Brane kicks the gun from Proteus' hand, grabs it, and gets one shot off, as the shape shifting villain flees the scene. Despite his military training, Brane misses Proteus. Believing Ryder to actually be Proteus, Brane calls the police, who issue an all points bulletin for Ryder's arrest. Ryder hears the report over his police radio, and realizes that the clever Proteus has not only framed his Creeper identity for murder, but now, has also implicated his true identity. Remembering Sumo's last words, Ryder determines where he can find Proteus. Transforming back into the Creeper, Ryder catches up with Proteus in the midst of robbing the bank vault at the Rainey Trust Company. The Creeper quickly takes down Proteus' men, then corners the arch criminal. Proteus hits the Creeper with a paralytic gas, then requests his presence at Pier 14, midnight, the next day. With the gas worn off, the Creeper switches back to Jack Ryder, who is immediately arrested by police officers, who have responded to the bank robbery. Ryder is jailed, but after convincing Brane that he isn't Proteus, the station manager bails Ryder out.
The Creeper keeps his midnight appointment at Pier 14. Proteus gets the drop on the Creeper, but underestimates his adversary's inhuman agility. The Creeper disarms Proteus, and the two men begin trading punches. Back and forth the two combatants struggle, each man taking the advantage, but never holding it. In a moment of self doubt, Proteus cuts and runs, leaping down a manhole cover, into the sewer. The Creeper pursues. Proteus ambushes the Creeper from the shadows, but the Creeper quickly regains the edge, and chases Proteus into a dead end-- the bar covered entryway into the tunnel. With nowhere left to run, Proteus sustains a vicious beating from the Creeper. The villain manages to pull a bolo on the Creeper, which he easily dodges. Chance favors Proteus, however, when the errant spotlight of a passing tugboat momentarily blinds the Creeper. Proteus manages to bind the Creeper with the bolo, then beats him into unconsciousness. When the Creeper awakens, he finds himself tied to the bars covering the tunnel entrance. A torrential downpour is rapidly elevating the water level in the tunnel. Proteus reveals his true face to the Creeper, then turns and walks away, leaving his adversary to drown in the soon to be flooded tunnel.