In his office, Professor Xavier has managed to adjust Cerebro to focus on El Tigre just in time for him to witness his transformation into the Mayan god, Kukulcan. On the device’s video screen appears the image of the now golden skinned figure and, from the pendant around his neck, radiates sheer, unbridled power, as well as a nameless evil. Try as he might, Xavier is unable to get in contact with his students and, most disturbing, Cerebro’s readouts show that Kukulcan’s energies are rapidly increasing at an unbelievable rate.
In the city museum, Kukulcan too feels his powers growing. Never has a mortal held such raw, irresistible power, however he is a mortal no more. The essence of Kukulcan pervades his very being. Cyclops, still held in check by the museum guard under Kukulcan’s mental hold, thinks that either El Tigre has gone mad or humanity is in it for its greatest menace yet. No matter which it is, he needs to be stopped. Scott tries to reason with the guard a final time and slowly raises his hand toward the control stud of his visor. Then, with a sudden move, he opens it, releasing an optic beam that destroys the guard’s gun. The shock seems to release him from Kukulcan’s thrall, but Scott doesn’t have time for pleasantries or explanations and pushes the confused guard aside, going after the man formerly called El Tigre.
However, before he even has the chance to sneak up him, Kukulcan turns to Cyclops, having sensed the guard breaking free from his control. Scott fires an optic beam, but it strikes Kukulcan’s amulet and is hurled back at him with double force. As Cyclops sinks unconscious, Kukulcan decides to let him live, so that he can tell of his defeat.
Just then, from another section of the museum, enter the minions of El Tigre. Ramon and Toloc report how they have defeated the other X-Men with trickery and, afterwards, begin to ask about El Tigre’s new clothes resembling the ceremonial dress of an ancient Mayan Chieftain. Reaching for the pendant, Ramon wonders what prize it will bring when they sell it on the black market, though Kukulcan doesn’t like to be touched. Backslapping Ramon, he tells the two Indians that El Tigre is now more. He orders the slight men to be gone from his sight, or else they will feel his wrath. However, the two men feel betrayed of their promised reward and prepare their weapons to fight him. As Ramon hurls his bolas and Toloc swings his machete, the museum guard quietly slips away to call the police. Kukulcan is rather unimpressed and, with one simple gesture, calls up an irresistible wall of heat and force, felling both Indians.
Kukulcan decides that there is nothing more to gain there. The museum is full of treasures which men call priceless, but the one prize worthy of his attention lays a continent away, in the very land where he found the first fragment of the Pendant of Power. While he makes his way to the roof of the building, he announces that the pendant’s powers had lain dormant, unsuspected, since the conquest of the Mayas four centuries ago, but now he will replenish and increase them by returning to their primal source. With one sweep of his arm, Kukulcan creates a sphere of sheer solar force around himself and then takes to the air. He heads towards San Rico and, within minutes, he already has passed the midwestern area of the United States. Two farmers recognize the glowing object in the night sky and wonder wether it is “one of them flying saucers”.
Meanwhile, Professor Xavier once more tries to contact his students and, with Kukulcan’s mental powers no longer interfering, reaches one of them, who is just coming around. It’s Iceman, his head is still hurting from his earlier impact against a stone wall, but, on Xavier’s command, he gets up and searches the museum for his comrades. He soon comes upon Warren, who still has the blowgun dart sticking in his head, but too is gaining consciousness. Bobby pulls the dart from Angel and tells him that he was lucky; it was only a sleeping drug and not some lethal poison. In another part of the museum, they are greeted by the Beast, who has already found the unconscious bodies of Cyclops and the two Indians. Hank says that, for once, he is happy that Jean is attending college, as this was hardly the X-Men’s finest hour. Xavier advises them to depart and leave the two Indians for the police.
(the next morning)
At Metro College, Jean receives a rather urgent call from the Professor, asking her to get some books on Mayan history and legends. Of course, Jean replies, though, after hanging up, she wonders why he didn’t call her telepathically, like he used to. She fears he perhaps no longer considers her a member of the group.
A little bit later, in the library, Jean runs into her friend Ted Roberts and another familiar face – Calvin Rankin, whom Jean only remembers too well as the Mimic. Ted introduces them to each other, unaware that Jean already knows him. Calvin politely greets Jean, but then asks if they have met somewhere before, as she seems familiar. Jean quickly says no, she has been attending a private school until recently and she knew everyone there. Ted then invites Jean to join them in the cafeteria, but she turns him down. However, she wouldn’t mind a rain check. Ted jokingly replies it will be raining at eight tonight and he’ll pick her up. The librarian chimes in and tells them to be quiet, while Calvin thinks to himself that he won’t rest until he knows where he has seen Jean before.
(ca. two hours later)
Angel, Beast and Iceman are standing around Xavier, who is showing them on a map where the stolen pendant had been found in San Rico. Jean arrives and expresses how much she missed the others. Xavier apologizes for interrupting her, but he needs to know if she brought the desired books. Jean confirms it. After all, the Metro College has a large collection of works on pre-Columbian America. It’s only now that Jean realizes that Scott is not among the others and Warren once again sees that Jean would prefer Cyclops over him.
Flipping through the volumes, Xavier quickly finds what he was looking for by looking in the index for some mention of the pendant. Xavier cites from the volumes that, according to old myths, the enchanted pendant grants its wearer the attributes of Kukulcan, the feathered-serpent god. However, the book also mentions the deadly curse, which once led to a holocaust of violent upheaval. The archeologists, however, did not believe in any of this and linked the legend to volcanic eruptions, which showered a Mayan city with tons of molten lava.
The professor points out that El Tigre demonstrated the legend to be true and decides the team needs to depart immediately. Iceman wonders if Scott is fit enough to make the trip, much to the shock of Jean, who fears that there is anything wrong with him. However, Cyclops enters the room, explaining that he must have some sort of immunity to his own blast. With the team, and especially Jean, being delighted of his quick recovery, preparations are made for the journey. Minutes later, the X-Men (sans Jean) are aboard a jet. During the flight, Scott makes a decision. As he could sense that Jean cares as much for him as he for her, he can no longer stay quiet. Once they return from this mission, he will tell her of his feelings.
As the plane reaches San Rico, its arrival is noted by a peasant. He wonders why it is headed towards the same direction from which came the call of Kukulcan.
(several hours before)
Kukulcan reaches the spot of the jungle where, as El Tigre, he discovered one half of the Pendant of Power. As he gently floats down to the ground, the energy sphere around him dissolves. In the not-too-far distance, Kukulcan spots a reflective surface on top of some sort of hill that is almost entirely covered by plants and vines. He recognizes this as the ultimate source of his powers and, with one dramatic gesture, the golden figure unleashes forces that unroot all these plants, revealing a huge serpent totem underneath. A staircase leads up to the serpent’s head and, on its top, resides the gigantic, diamond shaped Solar Stone. Next, Kukulcan uses his powers on the imposing idol’s surroundings and frees the once proud Mayan pyramids of any overgrowth, until the last remnant of unwanted vegetation has been cleared. Finally, clearing a road from the city of his ancestors to the open sea, Kukulcan announces that the recreated Mayan Empire is now fit for habitation, though it needs people. Taking place on a jeweled throne, Kukulcan feels the Solar Stone absorbing the rays of the sun, providing him with the raw power for his next move. He calls out to the descendants of the once proud Mayan race and none will be able to resist his command.
Almost at once, a hypnotic spell seems to grip a large number of San Rico’s population and they begin to trudge towards the restored Mayan capital. Soon, they are ordered to work in the long abandoned mines, digging for gold to provide the empire with wealth and the people are happy to serve. Within a few hours, even San Rican police, sent to investigate the reports of missing people, fall under Kukulcan’s thrall and serve the newly reborn nation.
The X-Men have set up base in a house near a river. Xavier tells his students that the portable Cerebro unit within the jet located Kukulcan a few miles up the river. As the Mayan god’s powers will prevent him from making telepathic contact, the team will be on their own. Cyclops ensures the Professor that they will do their best and Warren makes a snappy remark about the “originality” of Scott’s statement. As the team load a small boat with some equipment, the Professor once more reminds them that there should be no dissention in their ranks and Warren promises there won’t be any. He thinks to himself that he needs to get his ego in control; it’s just that he is jealous of Jean evidently preferring Scott. Warren apologizes to Scott, who then starts the boat's engine.
Not before long they reach a narrow point of the river and, all of a sudden, a jaguar leaps onto the boat from a tree above them. Iceman wonders if it has been sent to them by Kukulcan, though Cyclops knows that if that were the case, it would be a horde of animals and not just one. Bobby creates an ice-fork, temporarily holding the jaguar at bay and Angel takes to the air. He grabs the cat by its tail, lifting him up and throwing him to the river’s shore. Warren uses the chance to fly a few circles, though Scott calls him back to the boat. They can’t afford to get separated by any distance. The Angel obeys, though he doesn’t like it. However, there is no way he could explain the joy of flying to any earthbound being.
A short while later, the boat is approaching rapids and they are too fast to avoid hitting them. Even worse, there are cayman’s in the water. As the boat crashes and eventually sinks, Iceman escapes on one of his ramps and the Beast gets to the shore by using the rapids and one of the ‘crocs as stepping stones. Catching Scott, Warren says that this leaves only him to “nursemaid”, though the X-Men ‘s leader claims he was far from helpless. He isn’t that bad a swimmer and could have used his optic beams on the reptiles.
Having regrouped at the shore, Cyclops thinks that they must be near Kukulcan’s base and tells the Beast to climb up a tree and scout ahead. He knows the Angel would have a better view, but he might be easily spotted. From above, Hank confirms Scott’s suspicion, there are Mayan pyramids and a man-made road less then five thousand feet away. He wants to rejoin his comrades and slides down a vine, only it’s not a vine, but a Boa Constrictor. Fortunately, the serpent is as surprised as the X-Men and does not attack.
Walking through the jungle, the mutants are recognized by Kukulcan’s minions, who are already making plans of taking over not only San Rico, but all of Central America. When he is informed of his troops signaling the arrival of the X-Men, Kukulcan decides that he won’t be as merciful as in the museum.
Minutes later, the four teens reach the edge of the jungle and step onto a clearing. However, it’s a trap and they fall down a pit that was covered with grass. Swiftly, a net is spun across the hole, preventing Angel from flying away and several spears are pointed down at the four mutants. Scott orders Iceman to create a shield between them and the attackers, earning him another snappy comment from Warren. Cyclops doesn’t care and says they’ll get out of the trap, while Warren remarks “How? Like the charge of the Light Brigade?” Again ignoring his teammate’s hostility, Cyclops starts blasting a tunnel, though, in his thoughts, he wonders why Warren is behaving the way he does. He then comes across the possibility that he has guessed his feelings for Jean. Meanwhile, the others are crawling behind Scott through the tunnel and, Warren too has his thoughts elsewhere. He hates to sound like “a poor man’s Hawkeye,” but he can’t get over the fact that a woman would chose Scott over him. Finally out in the open again, the team sneaks up on the confused Indians who are still pointing their spears at the ice-shield, and push them into their own trap.
The four X-Men make their way to the center of the Mayan city, past a guard, whom Cyclops quickly disarms with his optic blasts. The humans run away and Kukulcan has to face the hard truth that their fear overcomes his mental hold over them. But little does it matter, as he will oppose the intruders himself. The Angel dive-bombs down, intending to wrest the Pendant of Power, but the Mayan deity is warned by his inner sixth sense and evades the maneuver. While he angrily fires his solar bolts after the winged X-Man, the Beast sneaks up on him, hoping that Kukulcan is too distracted to notice him. Indeed, he manages to leap within the amulet’s range, but the Beast can’t touch it. Suddenly, the pendant flares up, blinding him, and Kukulcan explains that no human can wrest it from his rightful wearer. As the amazed Beast received a punch in his face, Iceman lunges to the front with a spear made of ice, but an incredible heat wave emanating from the golden skinned godling prevents him from getting too close.
Weary of the failed attack, Iceman slumps to the ground near the Serpent totem, where he is met by the Beast, all the while Warren is keeping their opponent busy. Looking at to the giant gem stone, Hank begins to understand its purpose. He and Iceman climb up the stairs and, indeed, the glowing red-hot jewel seems to be made of the same material as Kukulcan’s Pendant. Hank suspects that it is empowered by the very sun itself and Iceman agrees, so he begins to cover it with a block of ice.
The Beast rejoins the battle and tells the Angel to make Kukulcan expend as much solar bolts as possible. Warren has no idea why, but he follows his teammate’s suggestion. Meanwhile, Cyclops has managed to sneak behind the Maya god and prepares to blast at him full force. Kukulcan is very well aware of Scott, but shows no signs of this, until he suddenly ducks right in the instant that the deadly ray of optic energy is released. Instead of meeting its intended mark, the beam hits the Angel, who immediately plummets out of the sky. Scott rushes to his teammate, who thankfully is still breathing. However, his concern leaves Cyclops open for Kukulcan’s force bolts and he joins Warren in unconsciousness.
Kukulcan then shifts his attention to the other X-Men and realizes that Iceman is trying to cover his power source. He takes aim and blasts a solar force bolt, but it fizzles out before hitting Iceman – too much of his energies have been spent. But he still has some power left and aims to the ground, hoping to shake Bobby off the giant statue. To his surprise, the effect is much bigger than anticipated. He apparently struck a fault line beneath the city, sending tremors through the very foundation of the mammoth pagan stela. The Serpent Idol begins to crack and the ground beneath it is torn asunder. Just in time, Bobby pole-vaults to safety and, from one of the trees, he and the Beast look in disbelief, as the fissure closes and once again the totem is out of sight.
While still everything is trembling and shaking, they see Kukulcan heading into the stone temple atop one of the pyramids, hardly the safest spot in such a situation. Beast goes after him and pulls him out, only it is no longer Kukulcan, but again the frail form of El Tigre. As the old Mayan city goes down in an inferno of flame and earthquakes, Iceman ties up the gem hunter, while Beast inspects the now defunct Pendant of Power – nothing more than a harmless piece of jewelry.
Nearby, they find the other two X-Men. When everything started to come down, Scott came around and pulled Warren to safety. Yet he is lying so still now, that Hank and Bobby fear that he is no longer among the living. Cyclops tells them he is alive and, before he can answer the other two’s questions of what happened to Warren, the fallen X-Man comes around and says, “It was Cyclops! He struck out at me on purpose!” Scott tries to defend himself, rhetorically asking why he would deliberately blast a teammate, but Warren knows a sufficient answer, “Because of Marvel Girl! You lover her too!” He then passes out again and Cyclops lifts him up to carry him away from the city. He knows the Angel was raving delirious, surely the others know that – but why don’t they say anything? Their silence accuses him. And then it occurs to Scott that it might be true. Could he have subconsciously been wanting to get rid of the rival?