Batman and his fellow Batmen meet at the headquarters of their organization, the Batmen of all nations. They turn to the new statues of their members only to realize that no one has commissioned any such statues. Joker bursts out of one of the statues and has his new teammates emerge as well: the Jokers of All Nations. The two teams fight it out and Joker goes after Batman with a flamethrower. A stray shot from Canadian Joker's exploding puck brings down the roof, trapping the other Jokers, while Batman knocks out his nemesis.
Aboard the JLI Watchtower, new member Captain Atom shows Batman, Aquaman, and Martian Manhunter his new public service announcement about how non-powered people should let superheroes take all the risks. The JLI is unhappy with their new teammate's arrogance, and Aquaman and Martian Manhunter take offense when Captain Atom says that isn't a suitable superhero because he has no superpowers. He points out that any super-powered villain could easily kill Batman. As the atomic-powered hero walks away, Batman explains to his teammates that Captain Atom is actual Nathaniel Adams, a retired Air Force captain who gained energy powers in an atomic experiment.
The JLI receives a trouble alert that the villainous Major Force is attacking the Pentagon. The heroes go there and Captain Atom insists on fighting his old foe, shoving Batman aside. Batman tries to assist but Captain Atom knocks his nemesis through a wall into a lab. Inside is the villain's goal: the Quantum Vacuum. Major Force dons it and drains Captain Atom's nuclear energy, rendering him a mere human. Batman gets Nathaniel to safety while Major Force flies away
As Martian Manhunter summons the rest of the JLI, Nathaniel insists on helping but Aquaman tells him to help. They beam up to the satellite and confirm that the Quantum Vacuum is a prototype energy drainer that can absorb nuclear energy. Nathaniel wants to help despite his lack of superpowers, pointing out that Batman is an active member. However, Batman says that it's not as easy it looks.
Major Force drains the energy of a nuclear plant, giving himself enough power to stop the other members of the JLI when they attack him. Meanwhile, Nathaniel tries to cope with a pickle jar and fails, and Batman tries to reassure him. However, the Caped Crusader walks away in disgust when Nathaniel comments that he feels like a loser, just like Batman. The former superhero reconsiders and asks Batman for his help, and Batman takes him to the JLI's hologrammatic training chamber. Nathaniel is unable to handle any of the supervillains that the JLI might face, or even a common bank robber. He's ready to give up until Aquaman decides to sing him an inspirational song about how heart matters more than powers.
Martian Manhunter receives word that the other JLI members have been defeated. He gathers Batman and Aquaman to teleport down, but they refuse to take Nathaniel with them. Aquaman puts him on monitor duty and they teleport down, but Major Force is too powerful for them to defeat.
Nathaniel decides to help anyway and flies down in a JLI plane. He crashes it into Major Force and momentarily delays him, but the villain imprisons the others, leaving Nathaniel to fight on his own. Nathaniel is powerless against him, but notes that Major Force's powers are out of control: the Quantum Vacuum has overloaded. It explodes, freeing the others and giving Nathaniel his powers back. Back to normal, he easily defeats the villain.
Later on the satellite, Batman compliments Captain Atom on his truly heroic spirit. However, Captain Atom explains that the lesson he's really learned is that people without superpowers are pathetic and fragile.
Captain Atom was originally a character created by Steve Ditko at Charlton Comics who first appeared in Space Adventures #33 (March 1960). He had a pretty undistinguished career, and eventually DC got the rights to the Charlton stable of characters. He first appeared (briefly) in Crisis where it was revealed that the Charlton "universe" was another of the multiple Earths. That Earth was destroyed and/or merged with all the others (don't ask) and Captain Atom became an established hero on Earth and appeared in Captain Atom #1. His origin here is different - in the comics he is encased in an alien metal as part of a government experiment. Captain Atom is the character upon which Dr. Manhattan of the Watchman graphic novel is based upon.
Clifford Zmeck first appeared in Captain Atom vol 3, #12, and was created by Cary Bates, Greg Weisman, and Pat Broderick. Zmeck was a USAF pilot tried and imprisoned for life for rape and murder. He was offered a pardon in return for undergoing the same experiment that created Captain Atom. Zmeck gained the ability to project "dark matter" as well as superhuman strength and invulnerability from the alien metal that he was encased in. One of his hands was blown off but he typically uses dark matter to recreate it. This is his first animated appearance.
Batmen of All Nations
The Batmen of All Nations first appeared as a group in Detective Comics #215 (January 1955). The original members included Bat-Hombre, Knight and Squire, Wingman, Man-of-Bats and his sidekick Little Raven, Gaucho, Ranger, and Legionary. They later took the name of the Club of Heroes and maintained a loose association. In the modern era, they were reinvented by Grant Morrison and their careers brought up-to-date.