Synopsis by Hans J. Wollstein
While Officer "444" (Ben Wilson) battles The Frog's seemingly limitless supply of henchmen, The Vulture (Ruth Royce) steals away with Nurse Gloria Grey (Neva Gerber). The Frog performs a bit of redecorating during the ensuing mayhem and Officer Casey (Jack Mower) and the "Flying Squad" arrive to find a sign proclaiming the premises to be those of the "Cohen & O'Brien Overalls Company" rather than the offices of Dr. Blakley. Back at police headquarters, "444" tells his captain (Lafe McKee) that he suspects The Frog and Dr. Samuel Blakley (Al Ferguson) to be one and the same. An important clue leads the police to the underground sewer caverns where The Frog has imprisoned the increasingly lunatic victims of Haverlyite. Also present are the mysterious "Professor Kalium," Gloria and Frank Haverly (Phil Ford), but in his attempt to rescue the latter two, Officer "444" is dropped through a trap door to the cavern below.