[In "David Starr: Space Ranger," a] tale of the seventieth century, Paul French ingeniously combines mystery with science fiction. His inventiveness and his use of picturesque details remind one of Robert Heinlein's books and, though his characters are not so fully developed as are Heinlein's, they are for the most part more individualized than in the usual story of this kind. There are moments, to be sure, when David Starr suggests the comic-strip hero, but he is convincing enough for the purposes of the story.