Mr. Calder and Mr. Behrens

Mr. Calder and Mr. Behrens are fictional counterspies who appeared in 24 short stories and 16 radio plays by the British mystery and thriller writer Michael Gilbert in the 1960s through the 1980s. Gilbert, who was appointed CBE in 1980, was a founder-member of the British Crime Writers' Association. The Mystery Writers of America named him a Grand Master in 1988 and in 1990 he was presented Bouchercon's Lifetime Achievement Award. Most of the stories first appeared in either the British magazine Argosy or the American Ellery Queen's Mystery Magazine, and were then collected in two books, Game without Rules and Mr. Calder & Mr. Behrens; One story, Double, Double, was later republished in an Ellery Queen paperback. Many of the stories involve finding, and dealing with, British traitors or deeply embedded foreign agents; a few take place in Europe; one particularly grim one is set in World War II, during which Mr. Behrens is the bomb-maker in a failed attempt to assassinate Adolf Hitler.

When Game without Rules first appeared in 1967, the noted mystery critic Anthony Boucher called it the second best collection of spy stories ever written, next only to Somerset Maugham's Ashenden: Or the British Agent. Later that year Boucher changed his mind to write that Game without Rules was even better than Ashenden.

Another appraisal comes from Barzun and Taylor's encyclopedic Catalogue of Crime:

The adventures of Mr. Calder and Mr. Behrens (and the Persian deerhound Rasselas) in the service of counterintelligence. There is clueing and detecting and danger and driving around, and (as one would expect) the storytelling is first-rate. But the genre seems to us more liable to repetition of effects than crime and detection. The best stories here include the longest, The Spoilers, and The Headmaster, not a school story.

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