In 2010 (slightly into the future when this was released,) the Holy Empire of Britannia (shown as all of North America on the map,) declared war on Japan.
Their war Mechs, the Knighmare Frames, defeated Japan's conventional forces.
The rig gets stuck, and a Britannian soldier mistakes Lelouch for a terrorist. Luckily, he's an old friend, but before they can get reacquainted, the stolen capsule opens.
It contains, not poison gas as rumored, but a girl.
The soldiers capture the girl, and make to kill Lelouch, but she breaks free and blocks the bullet.
As the soldiers invent an explanation for their superiors, she offers Lelouch a deal: he will get The Power Of The King, but it will isolate him. He can use it to escape.
Now, Lelouch stole one of the terrorist's communicators, originally intending to turn it over to the authorities, but now he uses it to rendezvous with the resistance.
There's no news of what's happening in the ghetto, which means they want to keep it quiet.
This means they can't call for reinforcements. Lelouch helps pick off Britannian Knightmares, and rescues Kallen. Conveniently, there's a train full of spare Knightmares. Lelouch makes an offer to the resistance: do what I say, and you can win.
Lelouch's Knightmare is still connected to Britannia's coms. He has the heading and location of all the other Knightmares on the battlefield. It's easy to set traps that way.
They break ranks to fill the gaps and get sucked into an even nastier trap.
Meanwhile, Lelouch's childhood friend Suzaku has miraculously survived the earlier fracas and has been recruited by Lloyd Asplund, head of special weapons engineering for Britannia, to pilot the experimental Knightmare, Lancelot.
With the ordinary Knightmare's losing to Lelouch's sigint advantage, now is the time for Lancelot to enter the fray.
And it's a monster. Suzaku has a massive hardware advantage. Worse, he thinks that if he defeats the terrorists and stops the fighting, he can rescue Lelouch.
In the second largest piece of tonal whiplash ever, we jump to school where the student council president is chewing out Lelouch for his absence yesterday.
And look who's come back to school! It's Kallen Stadtfeld, daughter of a wealthy family.
Lelouch arranges a meeting with the terrorists. (He wears a mask.) He wants them to switch from terrorism to actual war.
To prove himself, he arranges a demonstration of his ability to make the impossible possible: he breaks Suzaku out and throws doubt on the accusations.
Lelouch comes over to check on the accident, and gets trapped inside the rig when the terrorists decide to retreat.
Kallen, one of the terrorists, has a Knightmare in the back of the rig and takes it out to fight off the military pursuit.
She draws off some pursuers.