Demonic forces have possessed Halloween masqueraders—whose costumes look eerily familiar—and it's up to the Justice League to save the day. To help solve this mystery, they're joined by the Phantom Stranger!
The Phantom Stranger teases the tale about to unfold. In Rutland, Vermont a crowd gathers to hear Mistress Sarah pronounce the names of the doomed. At the witching hour, Mistress Sarah calls out the Batman, the Flash, the Green Arrow, the Green Lantern, the Hawkman, and Superman. These same six members of the Justice League of America assemble on board their satellite headquarters, believing they were summoned by the Batman. In truth, it is the Phantom Stranger who has brought them together. The Phantom Stranger reveals that Felix Faust is at large, in Rutland, Vermont. As mysteriously as he appeared, the Phantom Stranger disappears, despite the Green Lantern's efforts to restrain him.
A group of travelers develop car trouble, in route to Rutland, Vermont. The Justice League of America mount an investigation in Rutland, Vermont, but do not turn up Felix Faust. The Batman calls upon an old acquaintance, Tom Fagan, for lodging. As the annual Halloween parade is about to begin, Fagan asks the Justice League of America to ride the lead float, as the guests of honor. The Hawkman notices that the floats behind them, in the procession, have vanished. The crowds lining the streets stand stock still, as if paralyzed. The Justice League of America split up, into teams of two, to investigate the situation. The Flash, and the Hawkman, are attacked by a trio of costumed revelers, dressed as Adam Strange, Captain America, and Supergirl.
The demons possessing them grant them the powers, and the abilities, of the heroes whose costumes they are wearing. The Flash defeats "Adam Strange", only to fall to "Captain America". The Hawkman defeats "Captain America", only to fall to "Supergirl". The three demon possessed "super-heroes" fade away. The Flash, and the Hawkman, feel their life force slipping away from them. The Phantom Stranger appears. With the Hawkman pleading for help, the Phantom Stranger collects two items, then fades away. Felix Faust is pleased with the deaths of the Flash, and the Hawkman. The Batman battles against "Spider-Man".
The Green Lantern defeats "Spider-Man", only to fall to "Thor". The Batman defeats "Thor", only to fall to "Robin, the Teen Wonder". The Batman, and the Green Lantern, feel their life force slipping away from them. Again, the Phantom Stranger appears. With the Batman pleading for help, the Phantom Stranger collects two items, then fades away. Felix Faust is pleased with the deaths of the Batman, and the Green Lantern. The group of travelers search for one of their own. Superman battles against "Captain Marvel", while the Green Arrow battles against the "Golden Age Flash". The Green Arrow and the "Golden Age Flash" defeat each other.
"Captain Marvel" fells Superman with a bolt of magic lightning. Again, the Phantom Stranger appears, to collect two items, before vanishing. Felix Faust stands triumphant. The travelers search Felix Faust's secret lair, for their missing companion. As the witching hour strikes, the Phantom Stranger speaks each Justice League of America members' name, while casting an enchantment on a personal effect, culled from their costumes. The Justice League of America is restored to life. The Phantom Stranger has successfully counteracted Felix Faust's infernal sorcery. Felix Faust is immediately aware of the Justice League of America's revival. Felix Faust flees in the travelers' car.
The travelers are reunited with their missing companion, the girl who the demons cast as "Supergirl". The Justice League of America drives the demons out of Rutland, Vermont. Felix Faust is stopped by the police, due to a faulty muffler on the stolen car. His sorcerous power greatly diminished, Felix Faust is arrested, and taken into custody, by the police. The Justice League of America offer the Phantom Stranger membership in their ranks. Before they can finish voting him in, the Phantom Stranger vanishes.
(See Amazing Adventures #16 and Thor #207 for the other parts of this sly inter-company crossover.)