"Thanks for the warning, Caped Crusader." Martian Manhunter contacted Batman via Watchtower. "Our sensory array was malfunctioning. Scanning the object now." And with that, the mysterious ship was scanned. "Be careful." Batman warned. "It fired some kind of mind control beam." "But don't worry if you're brainwashed." Robin added. "You just need to be jolted by electricity to snap out of it. But it takes time to kick in."
Meanwhile, back in the Hall of Justice, the villains were ready to begin their assault. "We need to hurry before the real Hawkman arrives." Luthor warned. "Oh, don't worry, Lexie!" Joker said. "I already took care of that!" He then gestured to an imprisoned Hawkman back in the sewers, tied up and in a giant bird cage. As they approached the Slideways Teleporter, Firefly asked Grundy if he ever been to space. "AHHHH…...NO. ME NOT EVEN KNOW WHAT OUTER SPACE IS!" Grundy groaned.
At the Watchtower, the scan was complete. "It appears that your computations were correct, Dark Knight." Manhunter said. "The ship DOES come from outside this solar system." However, there was no response. Hal then checked the COMM signal. "The signal to Earth has gone down." He informed Manhunter. "It seems that the fault lies elsewhere." Martian Manhunter replied. "We can't fix it from here. I will require your assistance." Quickly, they headed to the meeting room.
Once the link was reestablished, the computer's alarms went off! "WARNING! UNAUTHORIZED USE OF THE SLIDEWAYS TELEPORTER!" The computer blared. Quickly, the two checked out the security footage to see villains invading the Watchtower! "We may need some assistance." Martian Manhunter said. He started the call. "Calling all Justice Leaguers! We have a Code-Red security breach in the Watchtower. Repeat, Code-Red! Report to the Watchtower immediately! Mayday! Mayday!" Cyborg got the call via radio in his bionics. He quickly flew up there. As Clark Kent, Superman heard the call via super-hearing, like someone shouting for help. He ran into the nearby phone booth, took off his glasses, and tore open his shirt to reveal the Kryptonian symbol of hope, his iconic S. After he had changed into his secret superhero identity, Superman got out of the booth, and flew upwards. When Wonder Woman got the call, she quickly flew upwards towards the Watchtower. When Barry Allen got the call via earpiece, he quickly became the Flash and, faster than a speeding bullet, ran towards the nearest Slideways Teleporter, mumbling something about never getting a break. Via the Batcomputer, the Dynamic Duo also got the call. "Caped Crusader, Boy Wonder, we have a security breach." Martian Manhunter called via Batcomputer. "However, due to security protocols, all entrances will be shut down." "Don't worry." Batman said. "We have another way."
After many preparations, the Bat-Rocket was complete! With the countdown at zero, the Dynamic Duo blasted off towards the Watchtower! At the Watchtower, however, Manhunter was holding off the intruders. Green Lantern, however, was to report to the alien ship and collect as much data as he could. "Surrender now." Manhunter ordered. "Surrender?" Firefly chuckled. "Not in my vocabulary, pal!" He then shot flames at Manhunter! The Martian then remembered that fire was his one weakness, and fell unconscious before the flames surrounding him. Lex tried to hack the systems, but to no avail. "It might help if you stopped playing games, Joker," Lex said. "And helped me get control of the main computer!" "But I LIKE games!" Joker teased as he playfully joy-buzzed one of his goons. Lex grabbed the buzzer and shocked the computer, granting access. However, he noticed the Duo approaching. As the rocket's top disengaged from the rocket, it transformed into an outer-space Batwing! Joker started the controls for his drone and piloted it into combat. He also hacked the Watchtower's weapon systems and fired at the duo! Robin jettisoned out of the rocket, and his pod became a fighter of its own as Batman's became one as well. However, the drone was easily destroyed. Joker managed to fire a mega missile at the two and, before they could shoot it down, it split into different missiles! Luckily, Superman was able to arrive and destroyed the missiles, buying the duo time to land at the hangar. Once they were inside, it was time to defend the Watchtower from the evil invaders!