"That bet, my dear," said Robert Thorpe with smiling eyes, "was very serious ... and it has had most serious consequences." He turned to the waiting men and extended a hand in farewell. "We are going to Europe, Ruth and I," he told them. "Just rambling around a bit. Our honeymoon, you know. Look us up if you're cruising out that way." Murder Madness PART TWO OF A FOUR-PART NOVEL _By Murray Leinster_ [Illustration: "_As the madness grew, the two men fought. They were murder mad. The local sub-deputy gave his guests the thrill of watching maniacs battling to the death._"] [Sidenote: Bell, of the secret "Trade," strikes into the South American jungle to find the hidden stronghold of The Master--the unknown monster whose diabolical poison swiftly and surely is enslaving the whole continent.] Seven United States Secret Service men have disappeared in South America. Another is found--a screaming homicidal maniac. It is rumored that they are victims of a diabolical poison which produces "murder madness." Charley Bell, of the "Trade"--a secret service organization that does not officially exist--discovers that a sinister system of slavery is flourishing in South America, headed by a mysterious man known only as The Master. This slavery is accomplished by means of a poison which causes its victims to experience a horrible writhing of the hands, followed by a madness to do murder, two weeks after the poison is taken. The victims get relief only with an antidote supplied through Ribiera, The Master's Chief Deputy; but in the antidote there is more of the poison which again in two weeks will take effect. And so it is that a person who once receives the poison is forever enslaved. [Illustration] Bell learns that Ribiera has kidnapped Paula Canalejas, daughter of a Brazilian cabinet minister--himself a victim--who has killed himself on feeling the "murder madness," caused by the poison, coming over him. Bell corners Ribiera in his home, buries the muzzles of two six-guns in his stomach, and demands that he set Paula free. CHAPTER VI In this room the electric lights were necessary at all times. And it occurred to Bell irrelevantly that perhaps there were no windows because there might be sometimes rather noisy scenes within these walls. And windows will convey the sound of screaming to the outside air, while solid walls will not. He stood alert and grim, with his revolvers pressing into Ribiera's flabby flesh. His fingers were tensed upon the triggers. If he killed Ribiera, he would be killed. Of course. And men and women he had known and liked might be doomed to the most horrible of fates by Ribiera's death. Yet even the death or madness of many men was preferable to the success of the conspiracy in which Ribiera seemed to figure largely. Ribiera looked up at him with the eyes of a terrified snake. There was a little stirring at the door. "Your friends," said Bell softly, "had better not come close."