The Covenant are invading Earth and have captured Colonel James Ackerson, a long time rival of Dr. Halsey and the SPARTAN-II Program. Under torture he reveals to them that there is a Forerunner treasure in Cleveland, the Key of Osanalan, that the Covenant need to activate the Halos. Living there is a lowly hotel concierge, Ruwan, who is caught in the middle of the Covenant attack on the city. He teams up with a random passerby, the musician Myras Tyla, and they struggle to escape before the Covenant kill them. But as they discover that the Covenant are holding back so as to discover the mysterious key, Ruwan starts to suspect he knows what it is...
The comic also co-stars the Master Chief, who is aboard the Forerunner Dreadnought and fighting the hordes of Covenant in there, all while hunting the Prophet of Truth.
While all four issues were originally supposed to have been published in 2007 for the release of Halo 3, numerous delays resulted in the series not being finished until 2009.
Halo: Uprising provides examples of:
- Action Girl: For a musician, Myras takes to combat like a natural, grabbing guns and taking out some Brutes with a spare grenade.
- Action Survivor: Ruwan isn't a fighter and barely makes it out alive through attacking aliens, incoming tanks, and ships falling from the sky.
- Aliens in Cardiff: The Covenant unexpectedly invade Cleveland rather than blasting it from orbit like any other city. Just as they would if a Forerunner artifact were there, and just as Ackerson expected they would.
- Asshole Victim: Considering how he's acted in every other piece of media in the Halo expanded universe, many would likely see Ackerson's death as this.
- Author Appeal: 26th century Cleveland has progressed from "The Mistake By The Lake" to a prosperous resort city, just like New Mombasa from modern Mombasa. In an interview with Marvel Spotlight, Bendis said that setting it in Cleveland was Bungie's idea (likely to tie in with the Halo 2 maps set there), but he liked it a lot since he grew up in Cleveland and thought it'd be great to write about it transforming from its modern mess to a place people love to vacation at.
- Batman Gambit:
Twyker: At this level, they're dumb worker bees with guns and armor. The second you hit 'em with something they don't understand, they panic and run to mommy.
- Colonel Ackerson lied about an artifact in Cleveland, counting on his brother to recognize the name of their childhood toy and fool the Covenant.
- When Ruwan is brought before the Covenant for a negotiation, Sergeant Twyker advises him to say that Ruwan is the Key, expecting it will confusing the Brutes enough that Ruwan will end up meeting with their top leadership at their command base.
- Covers Always Lie: The covers show Chief doing things he doesn't do in the comic, like piloting a Brute Chopper or wielding a beam rifle on some alien world.
- Even Evil Has Loved Ones: In all the previous Halo books, Ackerson acted like an arrogant and vengeful Jerkass. Twyker here was acquainted with him and calls him an asshole. But at the end of his life, Ackerson shows enough pity to give his brother a chance to either flee or hit the Covenant right where it hurts.
- Fourth Date Marriage: Ruwan and Myras grow attracted to each other over the course of their escape. She herself lampshades how little time has passed between them.Myras: We have the best meeting story ever! "Mommy, how did you meet Dad?" "Well, alien terrorists attacked my hotel and your Dad and I ran for your lives and we-" ...@#$%! What's his name again??
- Groin Attack: Chief gets out of a troublesome situation where a War Chieftain has slammed him on the floor by... sticking a plasma grenade to the Brute's nuts.
- Her Heart Will Go On: Myras tries to talk Ruwan out of going on this suicide mission and fleeing with her. He declines, and she promises to remember him in her music. She's last seen starting to write a new piece.
- Heroic Sacrifice:
- Ruwan volunteers to be captured by the Covenant while secretly injected with an organic tracking compound. Once aboard his location is triangulated so that an orbital MAC platform can target him, destroying a Covenant battlecruiser and its Prophet onboard.
- As for Ackerson, he dies taunting the Covenant for how utterly stupid they were to fall for his lie, and how many soldiers and ships they wasted going for it. Cue a Brute chopping his head off.
- I Am the Noun: In an attempt to stall the Covenant, Ruwan claims that he is the Key of Osanalan so that they take him aboard one of their ships.
- No-Sell: Chief pelts the Prophet of Truth with a hailstorm of carbine shots but, as with all High Prophets, his gravity throne's shields are too strong.
- Oh, Crap!: The Prophet of Truth has a glorious look of panic when he realizes "the Demon" is in his throneroom.
- Off with His Head!:
- When Ruwan and Myras drive a battered Warthog out of the city, an explosion flings a Brute's head onto the hood of their car.
- Hearing Ackerson taunt them about how pointless their efforts were, the Brute guarding Ackerson pulls out a sword and cleaves his head off.
- Pre-Mortem One-Liner:
Master Chief: It means... always strip your enemy of weapons before you interrogate him. (sticks grenade to chieftain's crotch)
- When Chief is caught by a War Chieftain Brute, the Brute demands to know what the "Key of Osanalan" means.
Ruwan: Kiss my ass. (MAC round blows up cruiser.)
- Ruwan gets one of his own to the entire crew of the Covenant battlecruiser Harbringer of Piety.
- "The Reason You Suck" Speech: Ackerson's last words to the Brute about to kill him:Ackerson: I gotta know... how much of your Earth campaign did you lose trying to find it? Come on, I really want to know... how many of you idiots did it take to screw in an imaginary light bulb? See, that's why you're going to lose. All your pomp and thinking you're so right about everything... when it comes down to it you're just dumb and arrogant and that's why we'll win.
- The Reveal: Ruwan reveals to the UNSC that he's Colonel Ackerson's brother and the Key of Osanalan is just from a game of pretend that they used to play when they were kids. Ackerson bluffed that it was a Forerunner artifact in hopes that the Covenant wouldn't shell Cleveland from orbit.
- "Shaggy Dog" Story:
- For the Covenant, their efforts to find the Key of Osanalan are wasted because it doesn't exist. They end up losing tons of soldiers, vehicles, a Prophet, and a battlecruiser all for nothing.
- For Master Chief, he's unable to kill the Prophet of Truth and is forced to leap off the Dreadnought before he's caught in the blast radius of a MAC station firing at it and a battlecruiser.
- Taking You with Me: The Covenant learn that Ruwan has been injected with a tracking device but mistakenly assume it's so the UNSC can rescue him. It's actually so the UNSC can bomb his location from orbit. And he's brought aboard a battlecruiser.
- Translation Convention: Justified. Whenever the story is from the Chief's point of view, he hears the Covenant's speech being translated into English. When it's from Ruwan's point of view, the Covenant speech appears as alien script.
- Wolverine Publicity: The plot mostly centers on Ruwan and Myras, with occasional brief cuts to Chief mowing down Covenant. Guess who's on all the covers?