Star Trek Mirror Universe: Glass Empires: The Sorrows of Empire

After the events in "Mirror, Mirror", mirror Spock tries to follow the vision of the Federation he saw in our universe's Dr. McCoy by asking mirror Captain James T. Kirk not to exterminate the Halkans. He realizes he has no hope of reforming Kirk and later strangles him to death in his quarters while Marlena Moreau watches. Marlena demonstrates how to use the Tantalus field to Spock on Kirk's body. Later, Spock listens to his human desires and keeps Marlena as the captain's woman, and then performs a mind meld on her. He begins plotting a revolution to destroy the Terran Empire and raise a new galactic order. 
Before the conference at Babel, Spock welcomes Sarek, whom he has not talked to in eighteen years, and the Vulcan delegates aboard the Enterprise and gives them a tour. He has a private conversation with Sarek in which Spock reveals his plan. He knows the Empire's fall is inevitable, but wants to preserve knowledge and to save its people by giving them freedom first. Spock will seize the throne and replace the Empire with a republic. He also reveals that Marlena is now his fiancée. 
Spock starts off his grand scheme by negotiating a treaty between the rival Elasians and Troyians. The Empire had seen huge deposits of dilithium crystals on both planets, but the planets were too well armed to be conquered, so they provoked a war to weaken the two races to conquer them when they had weakened each other. Spock convinces the Dohlman of Elas to wed the Caliph of Troyius and unite the two worlds to build up their economic power against the Empire. Elaan also grants Spock, not the Empire, exclusive mining rights of dilithium on her planet, guaranteeing Spock an admiral's position in Starfleet. 
Meanwhile, Montgomery Scott, Leonard McCoy and Nyota Uhura are discussing Spock's strange behavior ever since the Halkan mission. A while earlier, the Enterprise ran into a Klingon cruiser, but when a Starfleet boarding party beamed aboard, there were no Klingons aboard and it looked like they had just disappeared. The three of them suspect that Spock has Vulcan psionic powers, and Uhura resolves to kill him, but she is suddenly vaporized by the Tantalus field. Rumors continue to spread throughout the ship and the fleet, exactly as Spock plans. 
When word reaches Empress Hoshi Sato III, she decides to make Spock an admiral to gain his loyalty. 
Admiral Spock orders his first officer of the ISS Enterprise, Commander Willard Decker, to join him, Ensign Saavik, Lieutenants Xon, Solok and Stang at a Starfleet Admiralty conference on Deneva. The landing party goes to the security room, where Stang reports that there are no other admirals at the conference. Spock tells a dumbfounded Decker that he knows this is a trap. When the Vulcans are not looking, Decker tries to fire his phaser at Spock, but is stopped by the phaser-dampening field in the room. Saavik and Xon stab him and slit his throat. 
Grand Admiral Matthew Decker, Will's father, is furious when he hears the news that his son failed in their assassination attempt and is now dead. His first officer, Commander Hiromi Takeshewada, also informs him that he must contact the Empress as soon as possible. Sato orders him to kill Spock because they know he will seize control of Starfleet soon, and because of his popularity within Starfleet. He sends a message to the rest of the fleet loyal to the Empress telling them to assemble at the Terra Nova system and destroy the Enterprise. 
The Enterprise intercepts the encrypted message from Decker and moves to Terra Nova to "surrender". The ship arrives with shields and weapons powered down, and Spock offers to beam to Decker's ship, the ISS Constellation, to formally surrender. Once he arrives on the Constellation's bridge, the crew mutinies against Decker. Takeshewada, whom Spock had recruited for his cause years ago, relieves and kills Decker. Crews on all other ships throughout Starfleet have also mutinied, and Spock now has control of 61.3% of the ships, while the rest are captained by neutral officers. The Empress watches as Spock assumes the rank of grand admiral, and orders him to go to her palace next week so she can congratulate him. 
Right before the reception at the palace, Spock orders Saavik to his quarters. He asks for her thoughts about what he is about to do and decides she is worthy. He shows her how to use the Tantalus field and leaves the fate of the revolution in her hands. She has five minutes to decide whether to let the Imperial guards kill Spock and try to gain power for herself later, assassinate Spock with the field and gain favor with the Empress, or help him towards the future of the Federation he shows her in a mind meld. 
At the palace, Spock swears loyalty to the Empire, but refuses to swear loyalty to the Empress herself, which she uses as an excuse to kill him. Before her guards can shoot, the Empress and the entire company of the Imperial Guard are vaporized by the field. Spock seats himself upon the former Empress' throne, and after a few moments the crowd declares him their Emperor. 
Two months later, Spock has another conference with Sarek. They plan to increase the power of the Empire's governors and create a Common Forum and Senate. The Empire will begin offering planets the chance to join the Empire voluntarily instead of conquering them. After that, Spock wants to grant all sentient beings inalienable rights and eventually abolish the Empire.
Spock delivers the proclamation of inalienable rights, much to the joy of the people, but to the horror of the politicians. Spock and Sarek discuss his plans again, and now Sarek learns that Spock intends for the future republic to fall. 
While the Empire is in an uproar over the declaration of rights, Spock moves forward with his plan. He travels to Regula I aboard the Enterprise to meet with Carol Marcus about her proposal for more funds for Project Genesis. Right before the beam down, he and Saavik talk in the turbolift, where she also comes to the conclusion that Spock wants the future republic to fall, because he believes it will lead to the inevitable fall of the Klingon Empire. Spock denies Marcus' request for more funding, but drafts her into a top secret project. She is to terraform other caves similar to the Genesis cave in Phase II of the project for the future of their civilization.
The revolution is spreading throughout Vulcan. Vulcans randomly brush each other and pass on the vision of the Federation from the regular universe Doctor McCoy which Spock passed to Sarek, who passed it on to other Vulcans. One Vulcan about to spread the idea to another discovers a Romulan spy when she touches him, and then kills him.
Regent Sturka of the Klingon Empire gathers the High Council in the Great Hall. Councillor Gorkon grows weary of all the bickering, and Sturka's inability to control it, so he kills him. He wants to increase production on their moon, Praxis, and attack Earth while it is weak because Spock has decreased military spending and arms development. 
On Romulus, Praetor Vrax and the Senate are plotting their own strike on the Terran Empire. The Romulans know that a peace movement is spreading on Vulcan, but do not understand how. Senator Pardek, who has spies on Vulcan, voices his belief that the Vulcans are spreading the idea telepathically, which the Senators think is hilarious. He decides to vote to increase infiltration of the Terran Empire to try to understand why Spock is setting his Empire up to fall on purpose. 
Starfleet Admirals Lance Cartwright, Robert Bennett, Thomas Morrow and Salliserra zh'Ferro, Colonel Ivan West, General Quiniven, and the head of Starfleet Intelligence Commodore Vosrok meet and make a plan to stop Spock before he dismantles the Empire. After they kill Spock, Marlena, the Senate and the Forum, they want to reinstate the military dictatorship. They plan to take them all out in one blow by detonating a few kilograms of ultritium disguised as guard armor during a joint session of the Legislature. The admirals even have someone in the Imperial Guard who will do it.
Klingon General Kang is speaking at a conference between the Klingons and Terrans when the Terran ambassador, Curzon Dax arrives and rudely addresses him. The two empires had been fighting for control of the planet Korvat, but Curzon tells the Klingons that the Terrans no longer want to fight for the planet because the Klingons are so weak, the Terrans might as well just let them have it. General Chang informs Regent Gorkon that their bird-of-prey prototypes that can fire while cloaked are almost ready.
Marlena has a nightmare about losing her baby, and demands an answer from Spock when she wakes up about why he refuses to have any children with her. Spock says that any of their children would die violently because the time for the Republic's fall is nearing. And even if a child were to grow up in secret, their invaders would search throughout the Terran territory to find him, and they might uncover Spock's secret for the future. 
Spock and his guard, including Vosrok's assassin, travel to Khitomer to meet with the other powers in the quadrant about what to do now that Praxis has exploded. The assassin, Valeris, is assigned to be Spock's personal bodyguard during the conference. Spock offers a truce with the Klingons because their Empire cannot last much longer now, but Gorkon takes offense and refuses. The Klingon party quickly leaves Khitomer. Senator Pardek requests an audience with Spock, where he asks the Emperor why he will not form an alliance with any one of the powers and destroy the rest, and also why he is purposefully letting the Terran Empire be conquered in the future. Spock tells the Romulan that the fall of the Terran Empire will cause the fall of the Romulan Star Empire, the Klingon Empire and the Cardassian Union. 
Doctor Carol Marcus has been working on the secret project Memory Omega with her son and a few other scientists ever since Spock ordered the project nine years prior. Memory Omega, a huge network spread throughout the quadrant, is intended to store the sum of all Terran and Vulcan knowledge. Spock orders her to speed up the progress because he is running out of time; he predicts the Klingon-Cardassian alliance will destroy Starfleet in fewer than two years. When the war with the Alliance ends, Spock intends for Memory Omega to be the base of the people's new civilization. Carol thanks Spock for killing Kirk, because Kirk would have killed both Carol and their son David. 
Two days before Spock issues the results of the Khitomer Conference to the Legislature, he has a private meeting with Captain Saavik. He orders her to resign from Starfleet before his address and return to Vulcan. Saavik agrees because she understands that this is a part of his great experiment, which is ending soon. She says she will continue to serve him on Vulcan, but has something to take care of first on Earth. 
Two days later, Valeris is waiting in the Forum Hall for Spock to deliver his announcement. Right before she detonates her armor, she discovers the detonator is gone, and Saavik stabs her to death. Spock and his allies exposed General Quiniven and the other conspirators two months ago. 
In the proclamation, Spock renounces war and tyranny, abolishes the planetary governors, replaces them with elected presidents, and sends a draft charter to Legislature for review and ratification. Finally, he dissolves the Empire and replaces it with the Terran Republic. The head of the Republic is the Consul, which Spock will be for four years, and after he steps down he can be reelected or Legislature can elect someone else. Spock exits amid the crowd's shock and anger. He returns to his quarters, where, despite Marlena's protests, he vaporizes the Tantalus field.
Consul Spock and Marlena wait alone in the Common Forum for their killers to arrive. After the establishment of the Republic two years prior, it was quickly attacked by the Klingons and Cardassians. A year ago, Spock ordered unilateral disarmament of Starfleet and the people had no one to defend them when the Alliance invaded. The Alliance troops have just entered the Forum building. Gorkon and Legate Renar of the Cardassian Union break through to the Hall, and order Spock to surrender. Spock refuses, and tells the two leaders that that ending his Republic is the beginning of the end of their Empires before they assassinate him and Marlena. 
A week after Spock's assassination, the Alliance is reassigning Vulcans throughout their territories. Saavik, who had assumed an alias when she resigned two years ago, is assigned to be a domestic servant. Thousands of the reassigned Vulcans are sleeper agents, in a network that was built up over many years. They will hide in the halls and households of their enemies, and slowly destroy the Alliance and the Romulan Star Empire. She knows that their fall is inevitable now.