Synopsis / Summary / Plot
An ocean liner in the North Atlantic is about to hit an iceberg when a mysterious double beam of light flashes out and destroys the icy mass. The beam came from the eyes of Cyclops who is traveling to Europe with his fellow X-Men to meet Professor X for a mission. The Professor contacts them telepathically with his progress: he has discovered the hidden cave of his old enemy Lucifer in the Balkans and is searching the caverns by means of a hydraulic vehicle. Professor X is suddenly seized by a dust devil which carries him into the presence of Lucifer who shows the mutant leader a massive thermal bomb that will detonate should the villain’s heart stop beating. Meanwhile, on the surface the Avengers have arrived, following Thor who has detected evil energy impulses emanating from the area. The X-Men also arrive on the scene, to be attacked by an ionic ray unleashed by Lucifer. Escaping, the X-Men encounter the Avengers. The latter team suggests joining forces to seek out and defeat the evil, while the X-Men, warned telepathically by Professor X about the thermal bomb, find themselves fighting to stop the Avengers. As the two teams of heroes struggle, the captive Professor manages to exert a narrow mental shock wave to stun Lucifer. Once the villain is unconscious, the Professor contacts Thor to explain the situation. The heroes call off their battle and the Avengers decide to let the X-men handle the matter in their own way and they depart for home. Professor X brings his students into Lucifer’s lair where they attempt to defuse the bomb. With the Professor using part of his mind to keep the villain unconscious he guides Cyclops’ beam to destroy the fuse. Awakening, Lucifer vows revenge against Xavier but the Professor reminds him that the score is not yet even: Lucifer must pay for the loss of Professor X’s legs. He then allows the villain to go free since the X-Men are committed to peace.