The typical protagonist in these books was a boy in his late teens who was proficient in the art of electronics, a hobby that was easily available to the readers.

Riding the rocketship Sirius out of Port Goddard in the high mountains of New Guinea, Roy goes to the Inner Station, five hundred miles above Earth, for a two-week stay.

After listening to their talk about their home and seeing the pictures that they show him, Roy changes his future plans: he intends now that he will go beyond the space stations when he graduates from college and head out to the planets.

Anthony Boucher and J. Francis McComas praised Islands in the Sky as "a detailedly plausible and accurate fictional tour".

There he is introduced to the mysteries of gravity, acclimatizing, a misplaced atomic waste pile ship, monsters on Mars, space pirates.