Mike Foster, in the company of the beautiful Dallas and her killer brother, Kid Rodelo, has opened a saloon in Winnipeg, in the Canadian province of Manitoba, where the two young ex-outlaws can spend a golden exile, under the control of the redcoat Jim Brandon. But a couple of inexplicable crimes lead Colonel Brandon to call Tex and his pards for help. Kid Rodelo cannot be implicated, because he has lost the use of his legs and his left arm. So, who is the mysterious character plotting in the shadows with Mister Grant, director of the Fur Company in the nearby and rival town of Selkirk?... While Tex and Carson get to know the eccentric Doctor Marvel and his Chinese family, Tiger spies on the movements of Kid Rodelo, who knows and hides more than he wants to believe. During the night, an arson attack on the newspaper headquarters shakes Winnipeg, and Tex discovers strange, small footprints. Meanwhile, Kit Willer follows Kid Rodelo's trail to Selkirk and sees him enter the church on the edge of town... Without hesitation, Tex's son enters the church to spy on him... and thus meets his fate! Kit is missing! Having arrived in Selkirk on the trail of the dangerous servants of the "Dragon", Tex and Carson struggle to find the key to the problem, between an attack on the presumed culprit Grant, the involvement of Doctor Marvel, the mysterious identity of the self-styled "Dragon", a trail that leads to the city's underground... And it will be in the darkness inside the bowels of Selkirk, between illusions and drugs that have the power to confuse him, that Tex will finally find himself face to face with his enemy!
