Soaring through clouds of smoke, the Angel skillfully plummets between two criss-crossing pillars of searing fire. He emerges unharmed, though just barely; each time, the flames come closer and he knows the next time he might not be as lucky. It is another typical training session in the Danger Room that Warren is taking part in.
Below, on the ground, Warren’s teammates realize that he is in trouble and Cyclops orders the Beast to aid him. Not wasting any precious time, Hank uses a springboard to leap up high to the ceiling, above the smoke, where the Angel is rather surprised to see him. The Beast, though, tells him that there is no time for explanations now. He tells Warren to grab him, as the smoke thickens, enveloping the two X-Men. Before long, the Angel is flying blind and Hank wonders what their leader is planning below. Cyclops, meanwhile, directs Iceman to create a 20-feet-pole that reaches up to the ceiling. Eventually, the Beast’s sensitive feet find the guide pole and he grabs it, so that both he and Warren can glide down safely.
The exercise being over, Professor Xavier presses a few buttons on a control panel and, within seconds, the smoke is soaked out of the Danger Room, thanks to some high-powered vents. Xavier congratulates his students on their performance, especially the Angel. Cyclops agrees and says that he wants to add his own congratulations to Xavier’s – it will be great to fight side by side again. Warren thanks him, though actually he hopes that one day they could retire with there being no more evil mutants to fight. Surprised by these words, Cyclops can’t help but to think that Warren is a great guy, if only they weren’t rivals for Marvel Girl’s affection.
Iceman too comments about the team being back at full strength, despite the de-powered Mimic recently having returned to college. The Beast voices some concern whether Calvin Rankin can be trusted with their secret identities, as they only have his word that he would keep quiet about them. Professor Xavier has a surprise for the X-Men. Despite the worst of conditions, they did rather well against the Banshee and Ogre team-up, the Super-Adaptoid and the Warlock and, with Cerebro not having registered any more emissaries of Factor Three in the country, he has decided that the teenage mutants deserve the weekend off. Bobby and Hank cheer and start planning a double date with Vera and Zelda right away.
Warren looks forward to hop into his new mustang and asks Scott if he can drop him off somewhere, but the team’s field leader declines, saying that he will be helping Xavier with his experiments. However, Xavier tells him there is no need for that. In fact, he wants him something else to do. There are still the books on pre-Columbian civilization that Jean brought them and were never returned. Somewhat taken aback, Scott says that he’ll be glad to take them back to Jean, though he wonders why the Professor didn’t ask Warren to do it, as he sure must know that he admires Jean and would be driving around in his car anyway. As the X-Men leave to get changed, Xavier thinks to himself that, for months, he has known that Scott loves Jean but doesn’t dare to tell her, so maybe he can nudge him a little bit in the right direction. Besides, he wanted to be alone to pursue some experiments in private.
A little bit later, when Scott leaves the mansion, he finds Warren waiting for him in his car. Curious, Scott asks his teammate why he is still there and Warren admits that, at first, he planned to drive over to Metro College and look up on Jean, but he’s had it with being secretive, so he invites Scott to come along. Since Warren is being that honest, Scott finds that it is an offer he can’t refuse and gets in. As they are getting started, Warren says that they will make Jean chose between the two of them today.
Back inside, Hank McCoy is still getting dressed, putting on his oversized socks and shoes, which reminds him that, at the school, he might be an accepted X-Man but, outside, he is considered a freak. He is well aware that this is the reason he takes refuges behind a vocabulary, though he would give anything had he been born a baseline human. His thoughts are interrupted by Bobby Drake coming in, telling Hank that he called the ladies and they’ll be meeting at the Coffee A Go-Go.
At the same time, in front of Metro College, Jean Grey is talking to fellow student, Ted Roberts, who is expecting his older brother, Ralph, to show up. Ted is rather anxious to see him and Jean wonders why Ted feels such a rivalry with Ralph that he knocks himself out to excel at sports. Right then, Ralph arrives, driving a van, and proper introductions are made. Ralph compliments Jean on her beauty, telling her that Ted didn’t overstate when describing her. Next up, the three head for the stadium, which has been remodeled since Ralph left college. Once there, Ralph gloats that the school record for touchdown passes is still at the same mark he set years ago. Jean watches with concern, as Ted feels the need to prove himself and challenges Ralph for a pole-vaulting contest, as Ralph too holds the school record in that.
After a change of clothes, the two brothers start competing, Jean somewhat worried what kind of an effect losing in front of her might have on Ted. Ralph is the first to go but, in mid-air, the pole cracks and he knocks his head during the fall. Though his head aches, Ralph says he is fine and doesn’t need to see a doctor, worried that someone might learn that boy industrialist Ralph Roberts has gotten too fat for pole-vaulting. The three decide to skip the bet and move on to a diner near Jean’s dorm, where Ralph’s bruise and the Roberts’s sibling rivalry are soon forgotten. Jean learns that Ralph has worked for Tony Stark for awhile, until he started experimenting with cobalt and set up his own company, Roberts Research.
At this point, Scott and Warren drop in and while Warren is happy to see Jean again. Scott is brooding somewhat, now faced with not only one rival for Jean’s attention but two more in the form of the Roberts brothers. Again, after everyone is introduced, the group has some coffee, during which Ralph invites the others to show them around his labs. Jean and Ted are all for it, though Warren doesn’t like the idea and says he’ll bow out. Somewhat hesitant, Scott says he’ll come along to the labs, if Warren doesn’t mind. As night falls, the jovial quintet parts ways, Warren once more declining an offer to come with the rest. Secretly, he thinks to himself that there are other fair-haired fish in the sea and he is going to find them. Scott lightens up a little bit, thinking that, later on, he’ll get a chance to talk to Jean alone.
At the same time in Greenwich Village’s Coffee A Go-Go, Hank, Vera, Zelda and Bobby are listing to Bernard the Poet reciting his latest masterpiece, a poem comparing life to a yo-yo. The ladies marvel at Bernard’s talent and he soon approaches the table of them, having only eyes for Zelda and asking if he could join them. He gives her some compliments and Zelda invites Bernard to sit at the table with them but Bobby knows what the man is really after – a free cup of espresso. When nobody is looking, Bobby uses his power to freeze Zelda’s cup a few seconds before Bernard grabs it. The poet is slightly disturbed when he notes that the liquid inside is all solid and he quickly takes his leave.
Across town, Warren accidentally wanders into an electrified world of pop-twist teens and watusi-ing teeny-boppers. He asks one of the youths if this isn’t the Pizza Paradise, learning that it was until last week, when the location was remodeled into this nightclub, the Monkee’s Paw. Warren thinks that he might as well grab a girl and get in some shaking, when, suddenly, a female appears behind him and covers his eyes with her hands, telling him to guess who. He immediately recognizes the voice as that of Candy Southern, a friend from his childhood. Warren asks her what she is doing in the “big bad city,” both of them actually being from Nassau County, and she promises to tell him over a drink. Soon, the two have found a somewhat quieter spot in the club and Candy tells him how she talked her folks into letting her get an apartment of her own, that she wangled a job at the UN building and that she has been taking some night courses at Archer College. Halfway through, she realizes that she is running on about herself but Warren tells “Candace” to go on, he’ll have plenty of time later. She agrees, though only if he promises not to call her Candace again.
Meanwhile, the others have arrived at Roberts Research and Ralph shows them around. In one area, there are several models for ships that might be able to travel to Earth’s core, due to their hull being coated with a cobalt alloy, its melting point being at 1495 degrees Celsius. Jean and Scott are amazed by all this and Ted once more feels sorry for himself; there is no way he can measure up to his older brother. While Scott and Jean are busy looking at some pictures of Earth’s interior, Ralph excuses himself and takes Ted to another chamber to show him the most secret project he is working on. Before, though, he makes Ted promise to keep mum about it. Then, he activates he button and a panel slides open, revealing a blue and silver armor. Ted notes that it looks similar to the one worn by Iron Man and Ralph tells him he is right, only this suit is made of a cobalt alloy.
Ralph says the armor has only been tested once, but he wants to show Ted what it is capable of. As he helps his older brother to don the suit, Ted voices concern, as Ralph injured his head earlier and asks if they shouldn’t do it another time. Also, he asks why Ralph feels the need to compete with Iron Man. Ralph explains that he quit working for Stark Industries because Iron Man and Tony Stark refused to divulge the secrets of Iron Mann’s armor. However, as he observed the golden Avenger in action several times, he thinks he can duplicate most of the armor’s feats in a superior cobalt form and, if successful, he will turn the blueprints to the government. Stark claims that the suit’s power would overwhelm most men but Ralph thinks he is wrong, or lying.
Ralph tells his brother to stand back as he activates the cobalt armor and, instantly, torrents of cascading energy surge through the suit. He reveals that the suit can only be worn for two hours, as afterwards it produces the deadly radioactive cobalt 60. Then, to demonstrate the armor’s power, he points towards the ceiling, shattering it with a cobalt-powered recoil beam. Ted is amazed and compares it to Iron Man’s repulsor rays, though Ralph boasts that he surely is stronger. Next, he activates the built-in transistors and leaps through the hole he created, his physical strength increased a hundred times. As he returns, Ralph asks his brother what he thinks of his invention and Ted is sure impressed, though he wonders about the demolished ceiling. Ralph answers that such trivial things don’t matter to him; it can easily be repaired.
Suddenly, he begins to feel strange, his head aching terribly. Ted thinks that it must be an after-effect to his earlier fall and advises his brother to leave superheroing to the likes of Iron Man, at least for a while. Hearing this name, the Cobalt Man gets somewhat angry and tells Ted not to mention the name of “that costumed traitor” again. Ralph decides that he needs to seek out Iron Man and show him that he is no match for him. Ted understands that his brother is out of his mind and tries to calm him down. Remembering the two-hour-limit, he tries to help Ralph out of the suit but the Cobalt Man slaps him away. The impact of the metal glove is so hard that Ted Roberts passes out and falls down. The name “Iron Man” coursing through his mind, the Cobalt Man knows that he must find and destroy him, though first he starts destroying the lab so no one may learn the secrets of his cobalt armor.
When they hear the noise, Scott and Jean rush to the scene, both secretly cursing that their moment alone has been interrupted, as they were just making some progress and Scott about to ask her on a date. All this is forgotten, though, when they see the armored figure wrecking the lab equipment. Scott tells Jean to clear out, while he’ll change into costume and deal with the foe. However, the redhead says that she has her uniform in her suitcase and they are in this together. In record time, the pair get changed and return to the lab, or actually to a landing a floor above overlooking the room that the Cobalt Man is in.
Cyclops tells him to stop, and the Cobalt hesitates, saying that he finds the two of them familiar. Marvel Girl introduces themselves, while Scott is concerned about the Roberts brothers and what might have happened to them, having no idea that the Cobalt Man is actually Ralph. Having heard their names, the Cobalt Man recognizes the pair as X-Men, masked crooks just like Iron man, so he reasons they must be traitors too. He releases a force-blast at the catwalk the two mutants were standing on and Jean, comparing him to Iron Man, only adds to his fury. Cyclops leaps forward, grabbing a chain and safely climbing down, while Jean uses her telekinesis to levitate down.
Jean attacks the Cobalt Man first but finds that her telekinesis is not strong enough to do anything but hold him back. She yells for Cyclops to hurry, as it will take both of them to defeat him. Scott swings around on the chain, knocking the Cobalt over from behind, but he doesn’t dare to shoot an optic blast while he is still swinging, for he might accidentally hit his teammate. By the time he has finally reached the ground, though, the Cobalt Man is back to his feet and leaps out of the way of Cyclops’ optic rays. The Cobalt man decides that it’s time to take the offensive and knocks the support out from under a metal cab. The two mutants can’t get away in time and are both buried by the awesome mass of falling metal. Nobody else there to put up any resistance, the Cobalt Man gloats about his victory and then heads towards Stark Industries to finish his vendetta with Iron Man.
Luckily for Scott and Jean, the metal cab was hollow and Scott used his optic beam to blast a hole through the cab’s bottom. Though now trapped, both X-Men are unharmed and, with his power exhausted, Scott needs a while to recover. Jean asks how they can contact the others, when Scott reminds her of the new signal wrist devices the Professor recently gave the team. As Scott contacts Xavier, Jean thinks to herself that she can’t stop worrying about what happened to Ted and the danger they have just been in. She knows Scott is the born leader of the team, though about her own place among the X-Men she is not so sure.
The new wrist devices work perfectly and Xavier responds to the mento-call immediately. Being filled in by Cyclops on the current situation, he says that he’ll contact the other X-Men at once. However, the Professor can’t help himself, as he is caught up in some very vital experiments. Unbeknown to Scott, Xavier is in the mansion’s basement, in a room behind the mysterious oaken door.
At the Coffee A Go-Go, Hank and Vera are on the dance floor, among some other teenagers. They are dancing the Monkey and noticing Hank’s excellent moves, saying he is a natural. While Hank still wonders whether that was a compliment or an insult, considering the name of the dance, he receives Xavier’s mental message. He excuses himself, saying that he wants to ask Bobby for a few new steps, and quickly heads over to his friend, who picked up the message too. The two make another sudden departure, to which Zelda and Vera have gotten used to by now, though they don’t like it at all. Once outside, the two mutants wonder whether the ladies will be any more mad at them than usual but, right now, they have to worry about how to get to the location Xavier transmitted them. Hank calls a cab, well aware that his $1.35 won’t get them very far.
Uptown, at about the same time, Warren has told Candy as much as he possibly can about the private academy he is attending, each student having some special talent. In fact, he peaked Candy’s interest so much that she considers applying for a scholarship there too. Warren knows that he quickly needs to change the subject and asks his friend to show him some new dances. Candy joyfully agrees, though, right then, Warren too receives Xavier’s telepathic transmission. Much more polite than his two teammates, Warren excuses himself, saying that he just remembered an important errand he promised the professor he’d run for him, but he would love to see her again the next day. Candy takes him up on the offer and they part ways. A short time later, speeding through the night in his car, Warren thinks it a lucky break that he met Candy the same day he gave up on Jean – it’s almost like fate. No matter what will happen, he decides to make the best of it.
Back at Roberts Research, Scott knows that they need to free themselves and try to stop the Cobalt man before he attacks Stark Industries. He spots the hook and chain he used earlier and asks Jean if she could turn on its motor. Of course, she answers, and telekinetically activates the switch. However, not herself having thought of this, she blames herself once more, questioning if it is just because she is more worried about Ted than about stopping the Cobalt Man, or if her time away at Metro college has made her careless. Following Scott’s directions, Jean lowers the chain and then draws it closer for Cyclops to reach it and attach it to the metal cab they are stuck in. Reversing the motor, the couple is free in no time. Scott mentions that the Cobalt Man’s voice reminded him of Ralph’s and Jean agrees, though she wonders where the sense would be in him wrecking his own equipment.
The pair runs out of the lab, despite having no idea how to get to Stark Industries without any means of transportation. In front of the building, they find Ralph’s panel, which reminds them that Ted is still unaccounted for. Right then, they see him coming out of the building too, his head bandaged. Hidden behind the van, Scott and Jean hear Ted talking to himself about Ralph being the Cobalt Man and him wanting to stop him. Now knowing that their earlier suspicion was dead on, the two mutants secretly enter the van, thus solving their transportation problem.
Hank and Bobby find themselves in similar problems, the taxi driver having dropped them off as soon as he learned they could not pay for the ride. However, by chance, the next car passing by is Warren in his mustang. As Warren stops, though, it turns out that it wasn’t a coincidence, for Professor Xavier told him where to pick his two friends up. Not much later, they arrive at Stark Industries but the whole building is dark. Hank wonders why that is the case - after all, the factory is supposed to run 24 hours a day. However, then he remembers that the plant was recently destroyed and the new one is supposed to be dedicated this Monday.
After the car is carefully camouflaged and the X-Men have changed into costume, the Angel does an arial scan of the surroundings. He is spotted from below by the Cobalt Man, who, due to their similar costumes, links him to the two X-Men he earlier fought. He leaps upwards, straight at the Angel, who hears him just in time to evade the attack. The Cobalt Man fires several recoil blasts but Warren dodges between them. Below, the battle is observed by the Beast and Iceman, who try to catch the Cobalt man when he comes down to the ground, but they are a little bit too late, the Cobalt man having leapt away again. The Cobalt Man descends on top of a nearby bridge, now having the perfect vantage point to be safe from any surprise attacks by those he considers enemies. The three X-Men wonder what to do and who their opponent thinks he is, as he constantly accuses them of being traitors and to be in league with Iron Man.
Right then, Ted Roberts arrives in his brother’s van. The three X-Men tell him to drive away, saying that it’s not secure, but Ted reveals that the guy they are fighting is his brother. While Ted is busy talking, Scott and Jean sneak out of the van and join their teammates, hoping that Ted doesn't notice their arriving with him. Ted anxiously tells the mutants about the suit’s two-hour limit and the time being nearly over. The Angel realizes that they have to stop the Cobalt Man by any means, even if it means destroying him.
In precisely this instant, the Cobalt Man shouts at the assembled group that there is nothing they can do to stop him. In fact, there is more and more power coursing through his armor. As he starts to glow, the X-Men realize that the suit is about to become radioactive. As time is of the essence, Cyclops comes up with a desperate last-ditch plan and the X-Men spread out. The Angel takes to the air, circling around the Cobalt Man and evading his blasts. The Cobalt Man soon discovers that the Angel is only serving as a distraction for the Beast to crash the van into the bridge and he destroys it with a blast before it makes impact. Fortunately, Hank leaps out just in time.
What the Cobalt Man fails to notice is that actually both attacks served as a distraction for Iceman and Cyclops sneaking beneath the bridge and slowly climbing hand over hand to the other side. Above, the Cobalt Man has only eyes for Marvel Girl and the Beast again closing in on him, when suddenly his chest is encased in a block of ice. Before he has a chance to react, Cyclops fires an option beam at him. Though the beam doesn’t do any damage, its friction melts the ice around the chest plate. The Cobalt Man tries to leap away, to attack the X-Men from a different angle, but he finds his powerpack short-circuiting. As he plummets towards the river, the Angel quickly dives down and catches him just in time, for, trapped in the disabled armor, Ralph Roberts would have surely drowned.
Back on the shore, the X-Men notice that the armor no longer glows, a clear sign that the danger has passed. Ted helps his brother take off the helmet and finds that he is amnesiac of the events before. After Ralph is filled in on everything that happened, just because of the bump on his head, he sees that Tony Stark was right. Armor like that of Iron Man or the Cobalt Man is too powerful and dangerous for most men to handle. Ted gives him right and encourages his brother to go back to inventing again, possibly something that the world needs much more.
As the groups prepare to separate, Ted tells the X-Men that he and his brother are heading back to Roberts Research to check on the two guests they left behind, though actually he doubts that they have been bored in the meantime. As he says this, he suspiciously eyes Marvel Girl. Both Jean and Scott worry what he means by that line - could Ted Roberts have figured out that she is his fellow student, Jean Grey?