Nighttime in the maximum security prison holding Cain Marko, alarms go off,
and the computer shows danger warnings. The security guard alerts Captain
Stone, and he enters Cain's prison cells with a few doctors. They tell him
that the systems are going down one by one, and he says they can't correct
it down there - they'll have to initiate the override sequence upstairs.
They say that they can't – they're shut out – they got a major malfunction.
Stone says that he should make a call.

At the mansion, Xavier telepathically calls his students to gather
downstairs immediately. They do, and he apologizes for the late hour and
says that he just received an urgent summons from Captain Stone. The X-Men
panic and Evan asks if Juggernaut escaped, but Xavier answers he didn't – at
least, not yet – but his containment unit has begun to fail. Scott is all
ready to go, but Xavier says he'll be going alone – however, with Ororo away
in Africa and Logan out on the open road somewhere, he's faced with a
dilemma, which means he's putting Scott and Jean in charge. They tell him he
can count on them, and he thanks them and leaves. Scott suggests starting
the day with a little Danger Room calisthenics, since they're already up,
but the others say he's crazy and go back to bed.

In the prison, Xavier tells Stone that shutting down the security grid is
the only solution that makes sense, but Stone doesn't like it – what happens
during the twenty second reboot sequence? Xavier says that Cain's paralysis
shouldn't wear off that quickly, and Stone agrees to do it.

At Bayville High, Jean is eavesdropping as Taryn practically begs Scott to
let her see his eyes, but he refuses. Taryn tries guessing the color – blue?
brown? hazel? – he tells her to try red, it was a long night. She presses
him against the wall and asks for just one peek, but he firmly refuses and
she says she has to go. Before leaving though, she says that one of those
days she wants to know all of his secrets, and he says that that'll be a day
to remember. He then notices Jean and asks her how long she's been standing
there. She gets nervous and confused, and eventually says that she was not
spying on him. Scott realizes that she was spying on him and asks her if
she's jealous, but she denies and walks away. He smiles, seeing through the
act.

At computer class, the teacher tells Kitty she is amazed - most people can't
program such complicated game protocols without crashing their computer -
Kitty, on the other hand, have managed to crash three. Everybody laughs, and
Kitty apologizes, saying she didn't get much sleep. The teacher then notices
that Arcade is playing a computer game across the room, and Risty is
watching the game. Risty notices the teacher saw then and tells Webber he
better sign off, but Arcade doesn't listen, and the teacher turns off his computer.

After the class, Risty catches up with Kitty in the hall and asks her if
there's anything fun going on this weekend. Kitty says that there's nothing
– her ear's been to the ground all week, but the party circuit is dry. Risty
says that if they only knew someone whose parents were gone for the night,
they could throw their own party, and that gives Kitty an idea.

Later, Kitty tells Kurt, Rogue and Evan about her idea. The boys and Kitty
are very excited about throwing a party while the professor's away, but
Rogue reminds them of one problem – Scott and Jean. Kurt isn't worried,
though - what are X-Men if not problem solvers?

In the prison, a SWAT team is ready to fire at Juggernaut if anything goes
wrong. On Xavier's mark, Stone shuts off the security grid, and Xavier
starts programming the computer. He continues working as the lights shut
down and sparks are shot from the computer. An alarm goes off, and slowly,
Cain starts moving – opening his eyes, making a fist… Stone panics as
Juggernaut breaks the chains, but Xavier manages to finish the work just in
time and Cain closes his eyes and stops moving again. Xavier tells Stone
that he's afraid there's another problem – this malfunction, it wasn't an
accident – it was sabotage.

On a bank overlooking Bayville, Scott is leaning on his car. Duncan drops
Jean off near him and drives away. Scott asks Jean what's up – Kitty told
him Jean wanted to meet him there. Surprised, Jean says that that's what
Kurt told her. Meanwhile, Kurt teleports in the back and takes the pin out
of the ignition, while Kitty phases behind Jean and takes her cellular
phone. They disappear without Scott and Jean noticing them. Scott tells Jean
that he sees what's going on – she's being sneaky again – she wanted to get
him up here, but blame it on someone else – she really is jealous of Taryn,
isn't she? Jean is shocked to hear this, and tells Scott that it's not true
and orders him to take her home. They get in the car, but Scott can't start
the engine. This time it's Jean's turn to pay him back, saying that he lured
her out there and now he's conveniently having car trouble. He says it
wasn't his idea.

In the mansion, Evan welcomes Risty Wilde and Webber Torque to the party.
Arcade is very impressed with the mansion, and Risty takes him to show him
around. The place is already full of kids, including all New Mutants and
X-Men. They're all dancing and enjoying themselves.

Risty leads Arcade through a hallway, supposedly leading to the library.
They find the elevator, and Arcade asks where it leads to. Risty says it
must lead to where they keep the big computer Rogue was telling her about,
and Arcade, hearing the words "big computer", hurries down. They end up in
the underground part, and reach the door of Cerebro. Arcade sees the
electronic lock and says that it must be there. He takes out some sort of
calculator and hooks it to the computer. Risty asks him in bliss if he can
hack security codes, and he says all computers are the same. He manages to
hack it, and the door opens, revealing to their amazed eyes – Cerebro.

Jean searches her bag, but can't find her phone. Scott walks away and tells
her to come – there's one down the hill. She tells him to wait and brings
him back telekinetically. She then starts walking too, and calls him to come
after her.

In Cerebro, Arcade is examining the helmet. He manages to gain access and
make Cerebro accept him as a user, and Risty asks if they got games in
there. Arcade checks, and finds pictures of the New Mutants. Risty asks who
these people are, and Arcade says that maybe they're game characters. She
asks him to download the file, and he burns a DVD for her. He hands her the
CD and tells her to go away, and she says she'll go upstairs to make a quick
appearance, and then she'll be back. She leaves, and Arcade finds programs
for the Danger Room. He runs them, and a huge screen appears in front of his
amazed eyes.

On the road, Scott and Jean are taking a ride on a truck. Scott asks the
driver to slow down, but the driver says he got a schedule to keep. As he
turns, Jean falls on Scott. They smile.

In the mansion, an alarm goes off on Rogue's watch. A few minutes later by
the Danger Room, the X-Men have gathered. Rogue tells them that somebody
started up the Danger Room - she can't even get the door open. Kurt
teleports in to shut it down from inside, but gets hit with a laser. Kitty
phases in to see why he's not coming back, and finds him unconscious. She
exits and tells Rogue and Evan that Kurt's been hit, and they phase inside,
dodging lasers. Arcade, watching them on the screen in Cerebro, is convinced
that they're characters in a game. Spyke manages to get to Nightcrawler,
spiking all weapons along the way. Rogue gets to them too, dodging more
weapons, and they lift Kurt. Arcade activates more guns, and they drag Kurt
away. Shadowcat runs away from lasers, phasing through walls, and loses her
concentration and slams into a wall, falling unconscious. Spyke and Rogue
get to her. Nightcrawler wakes up and teleports the four of them out before
they all get smashed, and Arcade is annoyed that he let them get away. He
hits more keys on the keyboard, when suddenly an alarm goes off and the
computer alerts him that the system has been compromised - initiating Defcon
4.

Scott and Jean get to the mansion, and realize that the others are throwing
a party and they plotted to get rid of them. They apologize to each other
for suspecting they wanted to meet on the bank. Suddenly, all the windows
and doors in the mansion get sealed in metal, and the fountain starts
shooting at them. They run away in horror, and Scott switches to his visor.

In the hangar, the doors seal on Risty. She cries for someone to let her
out, but lasers shoot at her. She falls unconscious, and morphs, revealing
herself to be Mystique in disguise.

In the foyer, and kids haven't notices yet that they are sealed in. Amara
and Jubilee drag Sam and Bobby to dance.

Scott blasts a gun in the yard. They decide to get in through the launch
bay, and start running. They manage to get to the cliff, and Jean levitates
them to the waterfall. Cyclops blasts the door open and they enter. They
manage to destroy a gun and continue to the next room, where Mystique is.
She wakes up and hides as the two X-Men destroy the guns for her and
continue on to the following room. She takes the disc and leaves, smiling.

In Cerebro, Arcade watches the four young X-Men escaping Defcon 4. The X-Men
get trapped between two opposite fires, but the boys teleport and the girls
phase through the wall.

Cyclops and Jean get to the Danger Room, and Jean goes for the controls as
Scott blasts the weapons. Jean is shut out, though - all security has been
rerouted to one room: Cerebro. They see Arcade in Cerebro on a screen, and
Scott recognizes him as a friend of Kitty's. The other X-Men appear, and
Shadowcat tells them about Arcade and that he's a computer game nut, but she
doesn't know how he got into Cerebro. Cyclops says they have to get him out.

In Cerebro, Arcade finds the X-Men again, looking at him in a screen.
Nightcrawler says that Arcade saw them, and they all get electrocuted. They
escape, with Cyclops and Spyke ruining the weapons and cameras. Arcade
looses him view. The X-Men get to Cerebro, and Rogue absorbs Arcade.

Later, Kurt, Kitty and Evan say goodbye to their guests. They're sorry they
missed their own party and now they're left cleaning up after everybody, and
they got quite a mess to clean. Webber wakes up and apologizes to the X-Men
for going to Cerebro, but he couldn't resist that game. The X-Men are a
little confused, but Xavier enters and tells them telepathically that Arcade
thinks it was just a game – he knows nothing more. Speaking, he tells Arcade
that a taxi is waiting to take him home, and Arcade leaves.

Scott apologizes to the professor and says he takes all the blame, but
Xavier tells him that there's plenty of blame to go around, even extending
to a mystery guest. Jean asks if he's talking about Arcade, and Xavier says
that it's someone else - someone who orchestrated all of this including his
trip away just to gain access to the mansion - now it's up to them to find
out who it was and what they were after.

Mystique looks at the mansion, holding the disc. She morphs to Risty Wilde
again and leaves.