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Although briefly knocked off his feet, Martin Andrews (Herman Brix) survives the exploding manhole cover no worse for wear. Joan Whiting (Joan Barclay), meanwhile, saves Dr. Wu (Henry T. Tung) from yet another of Victor Poten's (Bela Lugosi) fiendish devices, a telephone receiver equipped with a poisoned dart. But Joan, unfortunately, seems to have forgotten this when, abducted once again by Poten, she dials Andrews for help and receives only screams and a death rattle in return.