Traveling aboard a generational ship and with no memory of Earth, the human race has devolved into a class system, pitting the privileged Crew against the abhorrent “Muties” who live on the upper decks where few crewmembers dare venture under fear of death. The Muties are cannibals, infamous for taking prisoners who are never heard from again.

As far as the crew is concerned, the Ship is the entire universe. There is nothing beyond. Their god is Jordan, creator of the Ship. The Regulations, written by Jordan, are law. Engineering manuals written by Jordan are considered sacred texts.

Enter young Hugh Hoyland, an imaginative and curious student of the sciences who occasionally joins his friends for escapades into Mutie country—until he, too, is taken prisoner. However, while in their company, Hugh learns the true purpose of the Ship and the destination of the human race. He is led to the Control Room on the highest deck and begins to learn the instruments for operating the vessel he comes to know as the Vanguard.

Returning to the lower decks, Hugh reveals what he’s learned to those he considers allies, only to be arrested for heresy. After a daring rescue by the Muties, Hugh forms a new strategy for convincing the Crew of the truth, but will his mission result in a bloody civil war?

At 128 pages, Orphans of the Sky is a fast and easy read that maintains a steady pace. Hoyland and his comrades are likable and the lead Mutie with whom they ally, the bicephalic Joe-Jim, displays a remarkable mélange of savagery, sympathy, and intellectualism.

My only complaint is the treatment of women as less than second-class citizens. The few that are mentioned are portrayed as mere burdens or distractions. This struck me as a lazy way of reminding the reader that “yes, we have women around here somewhere”, while making it clear that they contribute very little to this society.