Green Lantern Honor Guard Tomar-Re calls in the newly-appointed Hal to aid in his investigation of a Manhunter temple on a distant planet. Tomar-Re warns that if there are similar sleeper cells across the universe, it could represent a galactic catastrophe. Hal insists on going in rather than calling Oa and Tomar-Re follows him. The two Green Lanterns explore the temple and find three Manhunter androids just, like the ones that Hal fought on Earth. Tomar-Re has confirmed that there is no master communication system... just as the Manhunters activate and attack them.
The androids are capable of withstanding power ring attacks and the Green Lanterns split their fire. Tomar-Re distracts them while Hal topples a pillar on them, but the androids are undamaged. The Green Lanterns retreat only to find three more Manhunters waiting for them. Hal and Tomar-Re fight their way past them and realize that they need to consult the Guardians.
On Oa, Hal and Tomar-Re report to the Guardians but they insist that they destroyed all of the Manhunters and the few spottings are isolated incidents. Hal disagrees and insists that there is a controlling force, but Tomar-Re points to the lack of a controlling signal. Nonetheless, he believes that further investigation is warranted and the Guardians allow Hal to assemble a small team. Hal makes one request and asks for the use of the Interceptor. The Guardians reluctantly agree to release the ship into his care.
Kilowog is busy training new recruits when Hal arrives to recruit him. His former teammate passes, saying that he's happy guiding new recruits, and Hal offers him a wager. He'll fight his best recruit and if he wins, Kilowog goes with him. Kilowog agrees and calls over Ch'p, a squirrel-like GL. Ch'p leaps on Hal's face and then tosses him around and then makes short work of him. Kilowog agrees, explaining that he was going to go with him anyway.
The Lanterns board the Interceptor and discover that Aya has been replaced with Lanos, a Lightspeed Astronomical Navigational Operating System. He lifts off immediately and insists on maintaining control per Guardian regulations. Hal orders it to find Aya and Lanos reports that she is being subjected to dissection in just over two hours. They arrive at the Science Branch and Hal removes Lanos' database.
Kilowog approaches the Green Lantern on duty, Larvox, and demands his records. Meanwhile, Hal slips in and goes to the dissection room observation room. He then releases Ch'p from a carry case and the squirrel-sized Green Lantern slips in via the message tube. The GL on security duty, Chaselon, comes in and Hal claims that he's checking the power circuits. He distracts Chaselon talking about his power circuits while Ch'p replaces Lanos' datacore with Aya's. However, as Ch'p returns via the message tube, Chaselon sends a message capsule through, knocking him back. Ch'p finally gets back and slips away and Hal leaves just as the Guardian Science Director arrives. She goes in and prepares to dissect Aya. Lanos awakens and insists that he isn't Aya, but the Science Director assumes Aya is lying to protect herself and proceeds with the dissection.
Hal flies out and Kilowog dismisses Larvox and joins his teammate. Ch'p gives them the datacore and they return to the Interceptor, and find Tomar-Re waiting for them. He apologizes, explaining that Hal was correct about the master activation system.
As the Interceptor departs Oa, Hal plugs Aya in and she immediately asks about Razer. Hal explains that he's on sabbatical. Meanwhile, Tomar-Re informs them that he uncovered a low-level anti-matter pulse that is activating the Manhunters. He sheepishly agrees with Hal about bypassing the Guardians and they fly to the source of the signal on the planet Biot. The three Green Lanterns fly in and realize that it's the Manhunter graveyard. Tomar-Re detects the anti-matter pulse and the Manhunters below them activate and close in. Hal spots a building and they go inside to seal the doors and man a defensible position.
Once inside, Hal explains that the building is a larger version of the bunker that they found. Tomar-Re confirms that the anti-matter pulse is coming from the building and they find an automated factory building new Manhunters. Hal realizes that all of the buildings that they've found are manufacturing factories. One of the new Manhunters spots the Green Lanterns and attacks while the others burst in from outside. Hal orders Aya to open fire on their location and she brings down the building atop the Manhunters. Hal and the others emerge and Tomar-Re realizes that the anti-matter pulse is still functioning.
A giant figure emerges from the ruins of the factory, informing them that he has conquered an entire universe and converted the trillions of planets into anti-matter to feed his hunger. His Manhunter slaves will aid him in destroying their universe. The Anti-Monitor fires a blast of anti-matter at them and the Green Lanterns retreat as everything in the beam's path disintegrates. Hal orders Aya to fire again and she knocks him back but the Anti-Monitor soon recovers and returns fire. The three Green Lanterns head for the Interceptor and Hal generates a shield to protect the others from the next anti-matter blast. The energy blast penetrates the shield and disintegrates Hal without a trace.