That old master of SF, Robert Heinlein, knows [science fiction] well enough to make fun of it. Kip, his engaging hero [in Have Space Suit—Will Travel], saves the world from an invasion of bug-eyed monsters—or their equivalent—and then goes back to his part-time job as soda-jerk in a drugstore. Kip has a nice line in wise-cracking: he also has great courage and deep humanity—it is his humanity which responds to the wisdom and tenderness of the Mother Thing. The M.T. is a Vegan, small, graceful and feline, and above all comforting…. As the complex, powerful story develops, the M.T. changes and becomes infinitely more formidable, but her vast compassion grows proportionately and she becomes no less lovable.

A few other writers manage the science in SF almost as well as Mr. Heinlein; no one else has his lightness of touch, the gaiety which in no way diminishes his fundamental seriousness. No one else draws so well the American Boy—the Girl, too, for Kip is accompanied into remotest space by Peewee who is ten and a genius. Peewee, who carries a dirty rag doll called Madame Pompadour through a series of appallingly perilous adventures, is one of Mr. Heinlein's best creations. In her maddening sophistication, her dreadful temper, her aggressive prejudices, her vulnerability, he is always entirely convincing, totally human. She deserves the father who, of all adults, is able to believe the story of their adventures and who knows all the right strings to pull. Professor Reisfeld is almost as good as Kip's father, who pays his taxes in cash (tied in a bundle) once a year and gives his occupation, on the official returns, as "Unemployed Spy".

Like all the best SF writers, Mr. Heinlein makes the most fantastic of adventures acceptable by relating them to the everyday world. His relaxed, throwaway style, precisely geared to the first person narrative pushes the story on briskly to a good-humoured conclusion.