John Mulcahy's quiet evening is disrupted when his Arab servant, Ali, and a presumed-dead acquaintance, Erich Girtmann, burst into his room. Girtmann, visibly distressed and paranoid, reveals that he has been living under the guise of a Druse peddler after faking his death to escape from his enemies. He claims to have stolen a priceless artifact, Melek Taus—a brazen peacock idol revered by the Yezidees, a devil-worshipping sect.

Girtmann, seeking Mulcahy's assistance to hide from his pursuers, explains his harrowing journey across different cities while being hunted by the relentless Yezidees. He details how he managed to infiltrate the Yezidees' secret sanctuaries and eventually stole their sacred idol, believing it would bring him immense wealth.

As Girtmann unveils the idol, Mulcahy's servant, Ali, vehemently advises against getting involved, fearing the supernatural repercussions of handling such an evil object. Ignoring the warnings, Girtmann plots to negotiate a ransom for the idol with the Yezidees. Mulcahy agrees to help him, driven by a sense of debt for a past rescue.

Their plan to hide Girtmann in an old fortress outside the city soon unfolds. However, the Yezidees quickly track them down, leading to a tense standoff in the fortress. Mulcahy, caught in a deadly confrontation, manages to save himself and Ali by threatening to destroy the idol unless they are allowed to leave unharmed.

The Yezidees reluctantly agree, binding themselves with a sacred oath not to harm Mulcahy or Ali, and retreat with their idol. The story ends with the cult disappearing into the night, leaving Mulcahy and Ali to ponder the dark world they briefly entangled with.