Agent Sorn picks Zack up from Earth and together they seek other aliens who can speak in support of inviting that planet to join the Galactic Union, while the Gnairt and the Kiapa Kapa Syndicate try to stop them.

On a routine voyage aboard an Academy spaceship, thirteen-year-old Mason Stark and his fellow cadets are attacked by the Tremist, an alien race who have been at war with humanity for the last sixty years.

"Astrid and Stella are best friends and intergalactic heroes ... After drifting into a dangerous force field powered by misunderstanding, it will take total teamwork to get back on track! Once they've recovered from that detour, a run-in with a fur-miliar villain and the rescue of an intergalactic pop star are enough to keep things interesting for Astrid, Stella, and their trusty robot sidekick, Bobo. They just need to remember what's most important--friendship...