Ángel Berriatúa Álex Angulo is a Basque priest and professor of theology who confesses to a fellow priest that he intends to commit as much evil as he can. The other priest is stunned until Ángel whispers his reasoning; when the other priest agrees to help him, a large cross falls and crushes him.
Ángel then ventures into downtown Madrid, where he engages in a string of transgressions and disturbing acts. He appropriates money from a homeless man, jostles a street performer, and, in a harsh moment, tells a dying man to go to Hell while pocketing the man’s wallet. His journey leads him to a record store where he encounters José María Santiago Segura, a self-described Satanist and heavy‑metal enthusiast from Carabanchel. José María hands Ángel a tape from what he believes to be the most “evil” band imaginable and remains eager to play a larger role in Ángel’s plans. Their bond tightens as José María invites Ángel to stay at his mother’s boarding house, living alongside his mother, his grandfather, and the woman who catches Ángel’s eye—Mina Nathalie Seseña.
From there, Ángel becomes obsessed with a book written by the occult TV show host Professor Cavan Armando De Razza. Ángel is convinced the manuscript can teach him how to barter his soul with Satan, and he clings to a sensational claim found in a cryptic Bible verse that the Antichrist will be born at midnight on Christmas Eve. He enlists José María in stealing the book, and the plan is set in motion even as the store manager remains skeptical of Ángel’s tale. When the moment arrives, Ángel flees rather than face disbelief head-on.
The plot takes a darker turn as Ángel and José María kidnap and bind Professor Cavan, pressing him to disclose the exact steps needed to perform a ritual that supposedly requires the blood of a virgin. Ángel first targets Cavan’s girlfriend, Susana Maria Grazia Cucinotta, attempting to obtain what he believes will be the necessary virgin blood; a mistaken blow renders Susana unconscious, and Cavan concedes that she is not a virgin after all. Undeterred, Ángel returns to the boarding house to pursue Mina, but José María’s mother interrupts the plan with a shotgun. Ángel evades the danger, escapes with a portion of Mina’s blood, and tragedy strikes when he accidentally kills José María’s mother. The trio manages to burn part of their evidence, consume LSD, and proceed with the ritual, which Cavan quickly suspects is a fabrication. A mysterious he-goat appears and vanishes, leaving Ángel with a taunting message written in the ashes: the devil mocks his failed deception. The trio flees as the police close in on Cavan’s disappearance.
Driven by fear and insistence on a sign, Ángel and José María race through Madrid in search of guidance about the Antichrist’s birth. Ángel confronts a speaker who theorizes about Nostradamus’s prophecies, triggering a chaotic chase in which three men dressed as the Wise Men are unrealistically gunned down by the police. He then heads to a heavy metal show in search of answers but is overwhelmed and beaten by the crowd. Meanwhile, on television, Cavan appears and implores Ángel to reach him, claiming he now understands why Ángel was right about the unfolding events. Cavan also interprets the devil’s symbolism as inverted versions of Christian marks, guiding them toward the Gate of Europe as a symbolic site.
The three confront a violent extreme-right gang that has taken over the area and has been terrorizing the city, murdering homeless people and scrawling “Limpia Madrid” across walls. The gang’s brutal leader is revealed to be the devil himself when he hurls José María off the building to his death. The gang wounds Cavan, but Ángel seizes a weapon and shoots them, eliminating the group as they were threatening a baby who is the Antichrist. In the ensuing chaos Ángel also shoots the devil. After the smoke clears, a new actor steps in to take over Cavan’s show, and Ángel and Cavan become drifting homeless men, wandering the streets. Cavan laments that they will never be able to tell anyone how they saved the world, while Ángel, reflecting on the strange turn of events, misses José María but accepts their fate as part of a larger, inexorable course.
