Andre Norton / Michael Gilbert
Librería Samer Atenea
Librería Aciertas (Toledo)
Kálamo Books
Librería Perelló (Valencia)
Librería Elías (Asturias)
Donde los libros
Librería Kolima (Madrid)
Librería Proteo (Málaga)
Ten-year-old Hal responds to a frantic S.O.S. from a group of friendly but timid space aliens held captive inside a mountain by the evil Ness. Hal, with the help of his cat Susie and the little Think-Think, the Stalker, and other small aliens, comes up with an ingenious solution to foil the plan of the evil Ness to take over the world.