After learning their field test is suspended because they aren't ready, the Space Cases try to prove themselves by making contact with the Christa, an alien ship outside Star Academy. While Commander Goddard and Miss Davenport look for them on the ship, the Christa is pulled through a spatial rip sending them all on a journey they learn will take over seven years to return home.

After rescuing a teddy bear from Space for Rosie, Radu discovers a plot onboard the ship. But is it true or is he just imagining it?

The students are just beginning to get used to their lives onboard the Christa. But wait, are those torpedoes heading toward the ship?

After playing a practical joke on Commander Goddard and Ms. Davenport, the crew of the Christa find out what their twelve-year-old selves were like when they turn into kids.

After Harlan tells Radu he's going to pretend that Radu's invisible, Harlan himself disappears. He soon finds that the ship's crew is in danger and he can't do anything about it. Will Harlan be able to inform the crew before it's too late?

After getting into a fight, Catalina's invisible friend Suzee disappears and Catalina inadvertently puts the ship in danger. Will Suzee come back and help save the day or will Catalina find she can do it on her own?

When Bova announces it's his birthday, Radu says it's his too, out of jealousy because he doesn't know when his birthday is.

The crew gets a message from the future, but because of an ionic storm, much of it is incomplete. Catalina starts assuming things and gets the rest of the crew to put Harlan on trial. Meanwhile, it seems that the crew has slipped into a parallel universe where everyone is Spung, and now they have to run from Commander Goddard and Miss Davenport while still trying to figure out the message from the future!

Sofiana, aka Jack, a prisoner of the colony Luff, sneaks aboard the Christa and switches places with Catalina. They later find out Catalina is about to blow up! Can the crew save her in time?

Dram, an old but sweet man, comes aboard the Christa, acting like he's from the Middle Ages, and mistakes Catalina for his daughter Mirabella. He also says there's a creature on board that is draining everyone of their energy. Is he just a crazy old man, or does he speak truth?

Bova and Miss Davenport hear Thelma talking one night, and find a secret room they never knew about. Bova and Miss Davenport explore it, but Miss Davenport disappears. Thelma then runs away. Can they get Thelma and Miss Davenport back, or will they have one less android and a computer for a teacher?

The Christa rushes to another ship, identical to the Christa. It's the sister ship and it had sent out a distress call. Commander Goddard, Harlan, Radu, and Catalina board it with Thelma, leaving the others to stay behind.