Brother Eye is a supervillain originating in DC comics and is one of the Justice League's greatest opponents.
Several years ago, the villain known as Doctor Light broke into the satellite headquarters of the Justice League of America. The only person stationed on the satellite at the time was Sue Dibny – wife of Ralph Dibny, the Elongated Man. Doctor Light attacked and brutally violated her – an act that would soon yield disastrous consequences not only for himself, but for the League as well.
The Justice League returned and were shocked to discover Light's crime. Unwilling to let such an act to go unpunished, several members (including Elongated Man, Hawkman, Green Arrow and Zatanna) decided upon an unorthodox means of rehabilitation. While the others held Doctor Light down, Zatanna used her magic to permanently alter Light's personality. Instead of existing as a psychotic rapist, he would now act as a slow-witted, clumsy super-villain incapable of overcoming even the most meager of threats.
As Zatanna completed her spell, Batman entered the satellite and witnessed what had taken place. The conspirators knew that they had to keep this a secret from the senior members, so Zatanna wiped Batman's mind clean of the memory of the event.
Years passed, and Batman's memory slowly returned to him. He knew now that he could no longer trust the Justice League and embarked upon a plan of action to keep an eye on them. Using money through various Wayne Enterprises subsidiaries, Batman created Brother Eye – a semi-autonomous artificial intelligence surveillance system. Equipping it with an anti-detection stealth system, he launched the satellite into geosynchronous orbit. Through the use of Brother Eye, Batman collected a massive database of information concerning every known metahuman on Earth.
A few years ago, the international eco-terrorist known as Ra's al Ghul succeeded in hacking into Batman's database system. He used the information supplied in his files to ascertain the weaknesses of the JLA members and thereby exploit them. The League succeeded in foiling Ra's' efforts, but their trust in Batman was forever shattered. The standing roster of the JLA at that time were not members of the original Doctor Light conspiracy, and had no prior knowledge of what had taken place. Batman did not openly reveal his knowledge of the conspiracy to his teammates at that time.
Maxwell Lord, the Black King of the intelligence cabal known as Checkmate, learned of Brother Eye's existence and found a way to hack into it. He rerouted the satellite's systems, so that they would respond only to his commands. Max Lord's initiative was to systematically weed out all metahumans from the planet, by way of sleeper agents known as O.M.A.C.s. Through the use of Brother Eye, Max was able to coordinate strategic attack patterns against super-heroes all across the globe.
Lords' reign came to an end, when Wonder Woman attacked him directly, snapping his neck. Following Lord's death, Brother Eye initiated an automatic program known as the King is Dead protocol, at which point it commanded all remaining O.M.A.C.s to scour the globe annihilating every superhuman it could find. Brother Eye broadcast video footage of Wonder Woman killing Maxwell Lord across the planet, turning public opinion against her. After this, Brother Eye initiated the final protocol "Truth and Justice", by having all the remaining OMACS invade and attack her homeland Themyscira to wipe out all of the Amazons.
It was then revealed that Brother Eye was wrested away from Batman by Alexander Luthor, Jr. and became an important part of Alex Luthor's plan to bring back the Multiverse. Luthor granted the satellite sentience, allowing it to evolve into a brain capable of directing the energies of the dimensional "tuning fork". Brother Eye became the only artificial intelligence capable to calculating the correct coordinates of where the tower should concentrate its energies.
It becomes the target of a superhero assault led by Batman himself, using the new Blue Beetle (Jaime Reyes) to negate its vibrational frequency and bring it out of hiding. Batman attempted to shut down the central computer while Brother Eye attempted to distract him with footage of the battle between Nightwing and Superboy-Prime. Ultimately the satellite was finally knocked out of orbit by Mister Terrific, shutting down the OMACs and releasing the hosts in Themsyrica. Brother Eye made attempts to bring Batman down with him, asking if he can ever truly trust the heroes again. Batman replied that he'll take his chances, and accepted Hal Jordan's help in getting to safety.
A portion of Brother Eye was later retrieved and rebuilt by Buddy Blank, a former scientist from Wayne Industries. This portion was located in NORAD's storage hanger and later meets the time-traveling Karate Kid who was seeking a cure for the Morticoccus virus, a 31st-century illness evolved from the OMAC-virus. Announcing that "the Great Disaster has come to me," the Eye directs Karate Kid to Blüdhaven. Soon after, it reactivates its offensive protocols and assimilates the hangar it is being held in, turning the people within the hangar into new OMAC cyborgs, and itself travels to the ruins of Blüdhaven and assimilates its infrastructure and the people within it, using the Atomic Knights and Firestorm as power sources. Later, it activates a Boom Tube and travels to Apokolips, where it assimilates the entire planet and attempts to obtain the Morticoccus virus from Karate Kid, who has also been led there. However, it is forced to flee Apokolips when attacked by the Pied Piper using the Anti-Life Equation.
After a length of time, Brother Eye returns to Earth's orbit and transforms Buddy Blank into a modified OMAC that heavily resembled to the Earth-AD version of Buddy Blank (aka One-Man Army Corps). Buddy uses his newly found power to save himself and his grandson from starvation in the Command-D bunker beneath Blüdhaven by breaking out of their bunker. After Blank (having returning back to normal) and his grandson walked across the barren city, it is implied from Buddy that Brother Eye will contact him again for a future need.
During the events of Final Crisis, Mister Terrific and the Checkmate organization were working to mount a resistance against Darkseid but seemingly don't have the means to do it. Sitting in despair in a Checkmate stronghold, Snapper Carr through his hopeless rantings gives Mister Terrific an ingenious idea. Using Sasha Bordeaux to make contact with Brother Eye, Terrific convinces the A.I. to help them, telling it that it will surely be destroyed if Darkseid indeed captures the world.
Realizing this, Brother Eye accepts Terrific's terms, and reveals that there are still millions of people infected with OMAC nanotech. These people, now mindless drones of Darkseid, are overwritten by Brother Eye and become OMAC soldiers under the command of Terrific. This gives Checkmate and him the means to forcefully resist Darkseid.
At the peak of the Final Crisis, Brother Eye (or "Lord Eye" as it called itself) prepared to leave the doomed Earth with his OMACs and the people of Command-D, and start a new society on Earth-51. To this end, he asked Renee Montoya to serve as the head of a to-be-founded Global Peacekeeping Agency.
In the Future's End continuity, Brother Eye took control of the entirety of planet Earth by assimilating humanity and the entire Justice League (except Batman and a few others) into his system as cyborg drones.
In the sequel series Batman Beyond (2015), by Dan Jurgens, Brother Eyeremains in control of the planet and is the main antagonist of the first six issues, being fought against by the a human resistance faction lead by Maxine Gibson, Barbara Gordon, Micron, and Batman (Tim Drake). Brother Eye later assimilated Gibson, and captured Batman with the aid of Inque, who he was unable to assimilate, but was able to coerce into service by kidnapping her daughter and threatening to kill her if Inque did not serve him.
Inque betrayed Brother Eye when Tim Drake promised that he was able to rescue her daughter, and the pair later attacked the moonbase where Deanna was held captive, only to discover that Brother Eye's collective consciousness was all based in one android body. Drake fought the body but was unable to kill it, until Inque attacked it from the inside in her liquid form, and destroyed Brother Eye for good, albeit sacrificing herself in the process, in order to save humanity and her daughter.