After Brian Nightraider gets fired from the police, he gets a letter from the United Nation Immigration Bureau Special Task Force, "Marginal Service." He visits the address in the letter, only to find a bizarre occult shop.

Still on the fence about Borderlanders, Brian goes on a mission to find out the truth. In a red costume, he accompanies Zeno, Robin, and Bolts to Jukai, where the drug factory is supposed to be. On their way, their chopper gets shot down by a missile.

Brian and the team attempt to infiltrate Rubber Suit's mansion while he's holding a charity auction, hoping to retrieve a rare item being used to manufacture illegal drugs.

The team tries to crack a mysterious case involving terrorist bombings that seem to be following a clear pattern, but not a clear purpose.

The Marginal Service finds out that Rubber escaped to Higashino Island. They have to get there on a boat, but Cyrus isn't happy about it since he hates nature. Brian happily suggests a fishing contest. But what he manages to catch is a shark.

Brian and Zeno set out to rescue Robin and Bolts, who have fallen into Rubber Suit's clutches. Little do they know that Robin and Bolts are about to discover a secret about their past that will completely upend the mission.

The Marginal Service goes to the holding facility converted from a mall, where Rubber is being transferred. After Cyrus conducts a medical check up on Rubber, something strange starts to happen.

Rubber is in custody with the higher ups at the UN. Zeno is upset that he can't interrogate Rubber, and suspects that Theodore's hiding something. Zeno collapses and wakes up in Cyrus's lab, and everything starts to look shady.

Zeno gets caught up in the investigation of a missing child, but Brian worries that Zeno may end up going too far due to his troubled past.

Brian is desperate to find Zeno before the rest of the Marginal Service does, and his only choice is to seek information from... Rubber Suit?

Having heard the truth from Rubber, Brian is reunited with Zeno in Mt. Minakami and suggests to rescue children together, but Zeno doesn't listen. While they fight, the doomsday for the Earth, another Gray Shock is about to happen.