Into Medicine Hat, just before the year's big beef roundup, drift four cow-punchers from across the Border. Everything about Slick Jordan, their leader, stamps him as a dude, except the way he whirls a rope and handles his steel-dust broncho. When Jordan singles out Blue Pete for his attention, Inspector Barker, of the Mounted Police, has a hunch that trouble is about to follow in the wake of the newcomers. He learns how right his hunch was when Sergeant Mahon, Blue Pete's friend, reports on the strange happenings that delay the roundup. Blue Pete finds his time fully occupied keeping check on Jordan and his companions, who have hired out to the T-Inverted R and promptly ran foul of its foreman, Tully Mason. Secret attempts at murder and covert rustling across the Border step up the tempo of this new story in which the popular Blue Pete again proves that he can think faster than the next man, and that for him, at least, the dark expanse of the Cypress Hills holds no secrets.