[Ransom" deserves] mention for its portrait of the thoroughly amoral, egocentric Glenn Kirtland, a character unique in children's books, though not in life. Glenn, the high-school wonder boy, is one of the five teen-agers kidnapped because they live in wealthy Valley Gardens. The other four have conventional problems: shyness, divorce in the family, physical handicap and lack of self-confidence. As each reacts in his own way to being held captive atop an Arizona mountain, the predictable growth takes place—except in Glenn. It is this consistency of Glenn's personality that sets the book apart and makes it something more than another good mystery.

Dorothy M. Broderick, in her review of "Ransom," in The New York Times Book Review (© 1966 by The New York Times Company; reprinted by permission), June 5, 1966, p. 42.