When Captain Wataru Yuuki takes Big One into deep space to rescue a stranded space-train, he discovers two stowaways--his sons Manabu and Mamoru. Suddenly, the routine rescue mission turns into an all out war when an enemy Destroyer emerges from a White Hole. In order to combat the massive destroyer, Wataru has to resort to desperate measures. His sons and his crew can only watch as he makes the ultimate sacrifice.

Having lost both his father and his brother, Mamoru, in the line of duty, a brave Manabu still chooses to join the Space Defense Force despite his mother's protests. But while heading to SDF headquarters Manabu's space-train falls into a Time-Knot. Suddenly, Manabu finds himself standing face to face with Mamoru who has been dead for five years. Can Manabu change his brother's fate?

When Manabu is assigned to his father's old platoon in the Space Defense Force he doesn't receive the warm-hearted welcome that he was expecting. In fact, it seems that Bruce, a senior officer, is out to get him. Not only does Manabu have to make it through a life and death crisis in space, he has to survive Bruce's dangerously difficult training.

Is the Ghost Train called Eternity myth or reality? Sirius Platoon has to find out when a missing persons report is filed concerning a man who allegedly boarded the train; and when they come face to face with the massive specter, Manabu acts on impulse and jumps on board. But as legend has it, once you get on the Ghost Train you can never get off. Has Manabu sealed his own fate?

When Sirius Platoon is sent to Planet Leo Glando to investigate a crashed cargo train, they fall into a trap and Big One is stolen! Unwilling to let Big One remain in enemy hands, Headquarters orders Captain Bulge to destroy his own train. As the thieves race to get Big One into space, Sirius Platoon and Spica Platoon must hunt them down! Is there any hope of saving the legendary Big One?

A strange glowing sludge besets a passenger train in deep space. Suddenly the train explodes! Manabu arrives upon this grisly scene unaware that the true horror has yet to take hold. Will Manabu's nerves shatter? Or will he be able to separate emotion from duty?

After receiving a telepathic pick-me-up from Layla, Manabu is determined to regain his position with the crew of Big One. A criminal's master plan is revealed as SDF HQ is under assault. With all trains dispatched across the galaxy, can anything be done to thwart the destruction of the galaxy's prime peacekeeping force?

Manabu finds himself in the doghouse once again only this time his punishment is to help the SDF's head mechanic, Whitman. It doesn't take long for Manabu to see that attending Whitman's School of Hard Knocks is downright dangerous. And when a strange twist of events thrust the two hard-headed mavericks on a vital mission together, Manabu finds out what makes the cantankerous, old Whitman tick.

While waiting for an Electromagnetic Storm to clear, the crew of Big One passes the time by immersing themselves in the local culture. They encounter Salye - a magical creature with the ability to steal people's memories. Bruce falls prey to Salye's unique gift but soon learns the value of each and every memory.

Yuki, the Sexaroid Medical officer assigned to support the crew of Big One, doubts her worth as a fellow crew member. When news breaks out of a prison train escape at an isolated Space Junction, Captain Bulge is forced to alter Big One's course and tend to the situation. It is a race against time as the Sirius Platoon splits up to find the four desperate escapees. Manabu, teamed up with Yuki, are on the trail of the two prisoners. Will Manabu prove to Yuki that her worth is far greater than she expected?