Firestar enters the Danger Room. As a former X-Man she knows what to expect, robots and holograms that will test her fighting skills. The scene is an imaginary space station, and four robots have followed her in. She makes quick work of the first three, but the final one gets the best of her by turning off the gravity and opening an airlock. Firestar tumbles into space.

The voice of her old mentor, Professor Xavier, brings her back to reality. “The test is over Firestar, and you failed,” he chastises. Xavier warns that next time the threat could be real.

Xavier’s voice comes from the control room above the Danger Room. Professor X is with Spider-man, Iceman, Cyclops, Sprite, Thunderbird, Colossus, Storm, and Nightcrawler. Firestar joins them. Iceman comforts his teammate by reminding her of one of his own training mishaps that left the X-Men “picking ice cubes out of the Danger Room for weeks.”

Outside unnoticed by the group, an intruder performs an illegal override of the mansion’s securities to gain entrance.

Again inside, Spider-man requests a turn in the Danger Room. Beforehand, Cyclops reminds him that all the obstacles will only be holograms though they may seem real. The webslinger has difficulty but is very frightened when he smells ozone. He realizes that holograms don’t smell, so this must be real.

As Firestar descends from the control room to help him, Professor X tries to find out why Cerebro is disobeying him. Even with Firestar’s assistance, Spider-man still becomes trapped by a rogue Danger Room. An optic blast from Cyclops allows the friends to escape back to the relative safety of the control room.

Professor X fusses with Cerebro when face – half-human, half-robot – appears on a monitor. He introduces himself as Cyberiad. He tells the X-Men that the mansion and its defenses are under his control. When Xavier demands to know why his mansion is being attacked, Cyberiad replies that one person in the room already knows.
Xavier is able to locate Cyberiad’s position using his telepathy. He is in the attic, and the X-Men are in the basement; so the team must go through all of the floors of the mansion to stop him. With this information, Nightcrawler teleports away heedlessly.

Xavier scans the mind of his X-Men and Spider-man in an attempt to discover whom Cyberiad knows among the group. He stops when he reaches Firestar.

Firestar admits that she knows him. He was a physicist named Nathan Price. She helped him with his lab work. Also, they were in love. Once, criminals attempted to steal his work, but Firestar defended him. Unfortunately during the confusion, there was an explosion that burnt half of Nathan’s body. Nathan blamed Firestar for the accident, and they never spoke again.

Xavier reasons that Price/Cyberiad has entered the mansion for revenge against Firestar… and all the X-Men if necessary.

Next, Cyberiad is shown in the attic with Nightcrawler who is trapped in a plasma bubble. Cyberiad makes a hologram of Nightcrawler to trick the others. Nightcrawler (the original) pleads with Cyberiad to stop, and his Nathan Price half listens and seems to agree; but his machine half disregards Nightcrawler and overpowers his human half.

Back in the basement, Xavier warns the X-Men that they only have two hours to stop Cyberiad, or the mansion will overload. As he talks, gas seeps into the basement sending everyone into a coughing fit. Storm is able to ice over the grate stopping the gas. Sprite phases through the locked control room door and opens it from the outside.

Xavier decides that they would be most effective split into three teams: Colossus, Sprite, Cyclops; Storm, Iceman, Thunderbird; and Spider-man, Firestar, and himself. They head off their separate ways.

The fake Nightcrawler tricks the team of Iceman, Storm, and Thunderbird into a room that locks behind them. Nightcrawler disappears, and quickly the walls begin to close in triggering Storm’s claustrophobia. Thunderbird turns into a grizzly bear and knocks down the door. (To which Bobby cleverly remarks, “I didn’t know he could do that.”) The three flee the room post-haste and are safe for the moment.

An updraft traps Cyclops and Colossus in two separate rooms while leaving Sprite behind. Colossus attempts to punch his way out of his holding cell, but Cyberiad turns Colossus’s own strength against him and knocks him unconscious. Cyberiad makes another X-Men hologram, this one of Colossus.

Cyclops is trapped in a room of adamantium and is only able to escape by focusing all of his power into a small, concentrated ray and burning his way out.

Then, the fake Colossus tricks Sprite into a trap, a room made of vibranium which Kitty cannot phase through. (This prompts Cyberiad to quip, “I’ve grown accustomed to your phase.”) Fortunately, the escaped Cyclops is able to free Sprite as well.

Firestar, Spider-man, and Xavier reach the elevator, but Cyberiad disconnects the cable. Spider-man is strong enough to drag the elevator up the shaft though. When they reach the top floor they are joined by Iceman, Storm, Cyclops, Thunderbird, and Sprite. Suddenly, Professor X disappears into a room and Cyberiad’s clutches before the super-heroes can stop him. The X-men and Spider-man realize that the only way to Cyberiad is through the maze of madness, and they only have an hour left.

In the maze of madness, the fake Nightcrawler reappears; but this time Thunderbird reveals him as a fraud because when he teleports there is no smell of brimstone. Sprite then realizes that the Colossus who trapped her was also likely a hologram.

In the attic, Cyberiad again argues with himself. Nathan Price doesn’t desire revenge, but Cyberiad does.

Suddenly, Nightcrawler appears accompanied by the smell of brimstone. He claims to have escaped his plasma bubble. Nightcrawler leads the X-men right to Cyberiad and into a plasma bubble. This Nightcrawler was another improved hologram. Now the only one who is still free is Firestar.

Firestar escapes the maze and confronts Cyberiad. She burns him while apologizing that it had to end this way. But oddly Cyberiad doesn’t burn. It’s another hologram, and the real Cyberiad traps Firestar in a separate plasma bubble from the others.

Cyberiad leaves for his ship outside with the mansion about to explode. Meanwhile, Xavier instructs Firestar to reach the meta-battery unit and deactivate the plasma bubble. She does, but it only frees herself. On Xavier’s command, she departs after Cyberiad leaving the X-Men and Spider-man to free themselves.

The X-Men do escape by having Storm blast the other battery unit. They even use Colossus as a conductor to amplify the charge. Tragically, they only have a minute left before the mansion explodes and now it is all up to Firestar.

Firestar appeals to Cyberiad’s human half, but she is unsuccessful. So she is forced to burn the man she once loved into submission – saving herself, her team, and the mansion.

Afterwards, the Spider-friends depart from the mansion. Firestar tells Spider-man and Iceman the sad moral she has derived from all of this; you can fall out of love.