Doctor Fischer is not only a short novel, but an unsettingly spare one. I doubt if there is a detail in it, from lines of dialogue to what characters order for lunch, that does not contribute to the book's onrush to its final, and grim, moral point. (p. 375)

C. S. Lewis observed in Perelandra that truly Satanic evil is not romantic, black-caped, and thrillingly dark, but rather moronically, cruelly mindless and petty. And there is certainly a strong admixture of this kind of diabolism in the mysterious Doctor Fischer. But there is something else. His "experiments," godlike in their moral autonomy, are like the tests of a vengeful Jehovah eager to see, not who might be saved, but whom he can damn. At least since Brighton Rock Greene, good Gnostic that he is, has insisted that blasphemy and despair are at least second best to love and hope...