Mr. Calder and Mr. Behrens

Mr. Calder and Mr. Behrens are fictional counterspies created by the British mystery and thriller writer Michael Gilbert. They have appeared in two collections of stories, Game without Rules and Mr. Calder & Mr. Behrens. When Game without Rules first appeared in 1967, the New York Times 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.