Halo: The Thursday War is the sequel to Halo: Glasslands. In Glasslands, a team of ODSTs, a Spartan II, an AI, a scientist skilled in Sangheili language and lifestyle, and the Office of Naval Intelligence’s (ONI) successor is formed. They are called Kilo-5. The year is 2553, not even a full year after the Human-Covenant War ended in November or December of 2552. The humans and a shattered Covenant are trying to mend a fragile alliance. However, the Elites (Sangheili), are also having a civil dispute over their future. The Arbiter, a highly ranked Sangheili warrior who worked with Master Chief when the Elites and humans formed a temporary alliance, believes in peace with the humans, and reconstruction. A radical group of ancient monks called “The Servants of the Abiding Truth” believe in eradicating humans. They see humans as a parasite, and not worthy of life.
When ONI learns that the Elites are having difficulty deciding what to do, they act. They send three ODSTs (Orbital Drop Shock Troopers), a Spartan II (one of the few remaining original biologically augmented children), an AI from ONI’s headquarters on Earth, a scientist who’s skilled in Sangheili language, and the successor to ONI’s current leader (this successor just happens to be a rejected Spartan II. Not all Spartan II candidates came through the augments cleanly). Their mission is to supply the Elites with stolen Covenant weapons, and aid the radicals in their coup. That way, the Elites will be weak, and the humans can kill them all, and show who’s stronger. They must also stay under the radar of the UNSC (United Nations Space Command). The head admiral of the UNSC is pretty good friends with the Arbiter.
But, a human colony that wasn't affected by the war at all, Venezia, is a hot bed for human insurrectionists. Plus, to make things weirder, humans are living hand-in-hand with Kig-yar (Jackals), Jiralhanae (Brutes), and Unggoy (Grunts) on this planet. All three aliens species listed were part of the Covenant. The book doesn't say anything about these aliens being a part of the insurrection.
Anyways, at the end of Glasslands, the Spartan’s father happens to be on Venezia. Coincidentally, he’s the leader of the insurrection. The Spartan was kidnapped from her parents at when she was about 5 or 6 years old. So, she has no recollection of who her parents are, where she comes from, or anything else from her past life. The Spartan program, though effective, still causes some controversy among a few of the characters in the story.
Speaking of the Spartan program, the person who started the program, Dr. Catherine Halsey, is lost in a Forerunner Dyson Sphere. She made an appearance in Halo: First Strike, then she ran away with another Spartan II who was injured. She makes a second appearance in Halo: Ghosts of Onyx. In that story, a Spartan II is training the new Spartan IIIs. The Spartan IIIs are upgraded Spartan IIs and instead of being kidnapped by ONI, their orphans who want revenge for their planet, and fallen parents/friends/etc. The Spartan IIIs are also being trained by the man who trained the Spartan IIs. Halsey and the training officer, Chief Mendez, are constantly bickering. Halsey feels that Mendez has betrayed her. Mendez believes the Spartan III program to be better than the Spartan II program in many ways. Morality mostly.
At the end of Ghosts of Onyx, the Spartan II who was training the Spartan IIIs sacrifices himself to save Halsey, Mendez, the second Spartan II, and two teams of Spartan IIIs. The planet happens to be a shield world built by Forerunners, an ancient species of aliens who created the Halo Arrays with many other marvels the humans have yet to discover. The Forerunners died millions of years ago, so there aren’t any Forerunners in any of the stories. The planet of Onyx itself blows up, and Halsey and company are lost in a slip space bubble. Time is slower, and they have no contact with the outside world.
So, in Halo: Glasslands, they are finally found, and most return to Earth. Except Halsey. She is classified as KIA/MIA, and is under ONI’s custody.
And now we move into Halo: The Thursday War. In this story, the original plan to supply the Elite insurrection starts biting back. The professor, Professor Phillips, gets caught in the middle of the fighting. He was invited to visit Sangheili’s many marvels by the Arbiter, and he got stuck in a major city. So, the rest of Kilo-5 gets permission from the UNSC to rescue him. The Arbiter also appears to be losing his battle against the radical Elites. The admiral of the UNSC, Lord Hood, offers to help the Arbiter. The Arbiter accepts, and Lord Hood, Kilo-5, and the head of ONI (Admiral Margaret Parangosky) travel to Sangheilios. During the Human-Covenant War, and even in peacetime, the UNSC was building a new ship with Forerunner technology they've collected through the war. Though much of the ship is still under construction, it’s weapons and shields are up and working, and it becomes a unanimous decision for the UNSC to flex its muscles and show the Elites what they've been up to.
The ship is called The Infinity, and is the largest ship ever constructed. It’s so massive, there isn't a single dry dock big enough to support it! It can even hold UNSC frigates and carriers! Not only does the UNSC have a plethora of Forerunner technology, but they also have an alien species known as Huragok (Engineers). The Covenant utilized these aliens during the Human-Covenant War. These aliens are virtually harmless, and master tinkerers. They can fix any form of technology and make it look easy. They have tentacles, and float around like balloons. Their names correspond with how they float around when born. Even the Forerunners used these aliens when they still existed. As a matter of fact, they apparently created them. When Halsey was in the Dyson Sphere, they met a few Huragok who survived millions of years. Their mission was to wait for the return of Forerunners, and the Spartan IIIs tell them it’s been millions of years since the Forerunners went extinct. The Huragok opened the Dyson Sphere up, and ONI rescued Dr. Halsey, Chief Mendez, Kelly (Spartan II), and the Spartan IIIs. They also set up research facilities and learned the Huragok sign language. Huragok don’t speak, instead they use the sicilia on their tentacles as a form of sign language.
The Huragok played a crucial role in the construction of The Infinity, and also made improvements to Kilo-5’s frigate, Port Stanley. Lord Hood, and Admiral Parangosky attack the radicals, however, before the attack, Parangosky told Kilo-5 to secretly attack the Arbiter’s forces as well. That way, the radicals didn't get suspicious. Port Stanley is a stealth ship, and they were able to cloak themselves, and fire a few nukes at the Arbiter’s ships. When a few of the Arbiter’s ships go down, Kilo-5 blames it on a Kig-yar vessel. Kig-yar are notorious pirates, and they love to trade and make money. So, the UNSC left it at that, and were none the wiser.
Meanwhile, on Sangheilios, Kilo-5 (minus ONI’s successor, Captain Osman) save professor Phillips, and they have to recover the radical leader, Avu Med ‘Telcam. ‘Telcam is reluctant to go with them, but he couldn't protest, because Kilo-5 forced him to.
But wait there’s more! Another radical, Jul ‘Mdama, was kidnapped by Kilo-5, and sent to ONIRF Trevelyn (Dyson Sphere named after the Spartan II who saved it, Kurt Ambrose (Trevelyn was his real name)). Jul escapes through a series of portals, and finds himself on a planet with Sangheili populating it. Jul tells them of his mission, learns his wife died in the fighting, and gathers up an army to travel to Requiem. Another Shield World built by the Forerunners. However, this one contains the Didact. The Didact was an ancient Forerunner who despised humans and wants them all dead. Do you think Jul’s and the Didact’s view on humans jives?
Personally, I liked Halo: The Thursday War. Although the author seemed to ramble on, and on, and on, and on, and on, I liked it. The story is supposed to bridge the gap between the video game Halo 3, and the recently released blockbuster, Halo 4. Halo 4 takes place in 2557, and to anybody reading this who saw the end of Halo 3 or saw the headlines and TV commercials, yes Master Chief is still alive. Though, the UNSC doesn't know this until the events on Requiem (where Chief lands).
The book explained where The Infinity came from, and certain characters were, who would play a vital role in Halo 4. It also gave a little hint to the newly created Spartan IVs. Spartan IVs are marines who voluntarily chose to be a Spartan. No more kids. However, it’s unclear whether the soldiers are augmented or not. But overall, I highly recommend this book to anyone who is interested in the epic, legendary story line of Halo.