The four men who make up the Challengers of the Unknown travel to Dinosaur Island to investigate a strange meteorite that has crashed. They discover the meteorite just as Batman arrives from another nearby assignment and offers his assistance. A giant spider emerges from the jungle and attacks, and they realize the meteorite radiation has mutated it into a ravenous beast. Working together, the heroes defeat it and Batman moves on to his next mission. However, once he leaves, the meteorite splits open and star-shaped alien creatures emerge and attach themselves to the Challengers.
In deep space, Blue Beetle hears a distress call from a ship and goes to investigate. He discovers that Evil Star is attacking the vessel. The scarab armor attacks on its own and Jaime tries to talk with it while Evil Star returns fire. Running out of options, Jaime calls Paco on Earth, who is unaware of his friend’s secret identity. Paco is playing a Blue Beetle video game and isn’t happy at being interrupted. Meanwhile, Batman secretly watches from behind an asteroid. He interrupts Jaime’s call to ask what he's doing, but Blue Beetle insists that he’s busy. Paco finally checks and learns that in the video game, Evil Star powers his Starband using starlight. Blue Beetle generates an EMP to deprive Evil Star of his sunlight, and then beats him into unconsciousness. Batman emerges and says that the villain is down, and explains that he followed Blue Beetle to see if he’s ready to take on solo missions. Blue Beetle decides to Evil Star to nearby Oa and turn the villain over to the Green Lantern Corps.
Blue Beetle and Batman land on Oa. Guy Gardner and several alien Green Lanterns are waiting. They take Evil Star into custody, but then order Jaime to power down and turn the scarab over to them. Guy claims that Jaime is under the scarab’s mental influence. Batman tries to explain but the Green Lanterns knock Blue Beetle down. He fights back until Batman breaks up the fight and asks for an explanation. The Guardians summon them to their main chamber, where they explain that the scarab is a product of a race of alien conquerors, the Reach. They seed scarabs on planets. When someone finds them, they use them to become a hero. However, the scarab’s programming eventually supersedes their free will and forces them to become soldiers in the Reach’s assault force.
Batman believes that Jaime isn’t under the scarab’s influence. When Blue Beetle tries to leave, Guy creates an energy wall and recites his oath. He asks Jaime what he believes in. Unable to answer, Jaime breaks through the barrier and leaves. The Guardians decide to wait and see if Jaime falls under the scarab’s influence.
As he leaves, Jaime wonders if the Guardians are right. He suddenly finds himself in the armor's virtual reality. The scarab appears, apologizes, and takes him mentally captive, and explains that he belongs to the Reach now. The armor goes to the security control center, destroys the guardian robots, and prepares to go inside. batman arrives to ask what he's doing and the armor attacks him. When it stuns Batman, Guy Gardner attacks as well. The armor drives the two of them back, breaks into the control center, and takes out another Green Lantern. It then deactivates the planetary security shields, leaving the planet open to invasion. The armor then releases its control, leaving Jaime with no idea of what happened. They realize that Reach scarab soldiers are flying in, and demand that the Guardians surrender or die.
When Jaime refuses to join them, they take control of them again. The Guardians order the Lanterns into space to defend the planet. The armor blasts down Batman and the others, insists that Jaime no longer exists, and flies into space to join its comrades. The scarab suits begin their attack, and their technology make them greater than the Green Lanterns.
On the planet below, Batman and the others recover consciousness. Guy blames Batman, but the Caped Crusader notes that Jaime could have killed them but didn't, so he must have some measure of control. Batman prepares to fly into space.
The scarab warriors fight past the Green Lanterns and head for the Central Power Battery. The Lanterns are unable to stop them, but Batman grabs Jaime and tells him to draw upon his own personal willpower to overcome the Reach's mind control. When the armor prepares to kill Batman, Jaime tries to overcome the scarab's programming, insisting that he and it are stronger together as the best team ever.
Jaime finds himself back in control of the armor. He flies down to Batman and tells Guy and Kilowog to pour their ring energy into his armor. Guy reluctantly agrees but as they do so, the other scarab warriors attack. Blue Beetle feeds the lantern energy into them via metal tentacles, knocking them out and freeing them of their control.
Later, the Guardians take the other scarabs into custody. Blue Beetle refuses to surrender his scarab, and Guy speaks on his behalf. The Guardians agree to let Jaime keep the scarab, and Batman assures the teenager he's ready for solo missions.