Memories of people and places from long ago cause Bulge to reflect upon his life, as the crew of Big One embarks on a simple rescue mission. The feelings he thought were buried deep in his heart have surfaced. These newfound emotions have only lent an air of melancholy to a chapter of unrequited love in his life.

While evacuating a planet on the verge of destruction, the relief teams of Big One encounter a mysterious oasis unaffected by the catastrophe. As Sirius Platoon ventures in this unadorned world, they meet an elderly woman who mistakes Manabu for her son. The touching reunion reveals so much more than Manabu and his shipmates have bargained for.

When Manabu accidentally boards the 777 Express he runs into an old friend from his childhood days on Tabito. But there's not much time for reminiscing as the 777 falls under attack by aliens from another dimension. Manabu is prepared to fight to the death, but his friend is ready to throw in the towel and accept his fate. As Manabu duels the bloodthirsty aliens, he must also do battle with the doubt that is plaguing his old friend.

Manabu is confused when Louis tries to back out of their newly assigned mission: to guard President Drake of the Clarious Stellar Cluster. While on board the Dignity, Drake's posh VIP train, Manabu discovers the real reason that Louis didn't want to accept the mission. But personal issues are set aside when the deadly Secret Cyber Servicemen try to assassinate the President!

When the Orbit Network Radar confirms that a meteor stream is on direct intersecting course with Central Station, the SDF is sent to resolve this threat and save Central from utter destruction. Captain Julia of Spica Platoon tries to take the scientific approach, but Captain Murase of Vega Platoon refuses to wait and starts blowing up every meteor in sight. The friction between these two hardheaded Captains could light up a solar system! But can they depend on each other when their lives are on the line?

A casino train full of wealthy playboys and female attendants is beset by pirates and taken off course, crash-landing on Planet Guin, whose atmosphere rapidly corrodes metal. Sirius Platoon only has six hours to complete their rescue mission before Big One is completely eradicated. But the SDF's premier train isn't the only piece of metal risking to be scrapped! When Yuki jumps from a transport ship to save a survivor, her protective helmet falls off, placing her in extreme danger. Time has run out. Has this leap of faith decided Yuki's fate?

David meets up with an old flame when Big One is sent to rescue survivors from a small aircraft that crashed on a remote planet known as the resting place of the most beautiful jewel in the Universe. The Sirius Platoon soon comes face to face with a mystery that will prove that true love is stronger than dark, ghostly legends.

An intruder is on the loose at SDF Headquarters. Outsmarting his adversaries, this precarious assailant dodges custody and nearly takes Manabu's life. Against Captain Bulge's direct orders, Manabu hurriedly chases after Bruce to help track down his attacker. But when the intruder ambushes Bruce, hitting him with nerve gas, he is caught between life and death. As the effects start taking effect, Bruce receives a bizarre unexpected visit from an old friend. Can Manabu save him from the torments of his past, or is Bruce on the road to perdition?

The Sirius, Spica and Vega Platoons have all taken leave. Their vacation spot: Captain Murase's family-owned Inn on Planet Carcalla. Just when Manabu thought the best three platoons of the SDF were forgetting about their duty, absorbing everything from Karaoke to careless betting bouts, a loud cry from another guest sends the detached units into orbit. The guest's feline friend, Tiger, has gone missing! Orders are dispatched, supplies checked, forces ready to search, the SDF platoons must always adapt in any given situation. After an unexpected twist of events, Manabu realizes that moments of tranquility shouldn't be taken so lightly.

Manabu has been hand picked to join the Space Panzer Grenadiers, his brother's old unit. His sheer bravery and unparallel aptitude and skill make Manabu the number one candidate for the SPG, Galaxy Railway's elite division. While the team members of his old unit place their wagers on Manabu's return to Sirius Platoon, Bruce knows that it's ultimately going to be Manabu's decision of what path he chooses. During his final training session with the SPG, a magnetic disturbance strands Manabu onboard a damaged train all alone. During his strife, Manabu uses the pocketed encouragement of the Sirius Platoon to keep his mind clear and attempt to complete his mission. But will it be enough to get him back to his time-honored comrades?