Ranger Sam Burrack is riding to the Mexico Valley to hunt down the Arizona Cowboy Gang, notorious bandits who have topped the Most Wanted list for the past year. Now they're robbing banks and trains on both sides of the border. Burrak knows it won't be easy. He won't find the gunmen just waiting to be arrested in Bad River. But with patience - and a little luck - he will find them nearby, maybe in the limestone mountains, maybe in the caves above the old Quaker mission. He'll smoke them out like rats if he has to. That was the job, and a ranger always gets the job done.