Darwin LeOra Teilhet was born on May 20, 1904, in Wyanette, Illinois, of French Catholic stock. While a teenager, he visited the Correze section of France and worked as a juggler in a French circus. He also worked briefly on the Paris edition of The New York Herald Tribune. He was educated at Drake University, the Sorbonne in Paris, and Stanford University, where he met Hildegarde Tolman. They were married on October 28, 1927. His first two books, Murder in the Air and Death Flies High, had good reviews and good sales, but Teilhet was unsure of his path as a writer. He took a job with the N. W. Ayers Company as a copywriter, and for the next three years he concentrated on writing magazine articles and reviews. In 1934, however, he completed his best book, The Talking Sparrow Murders. The same year, James Poling of the Crime Club (Doubleday’s mystery imprint) asked Teilhet to write detective novels with a memorable protagonist. The result was Baron von Kaz. Around 1936, Teilhet became executive assistant to the president of Dole Pineapple in Hawaii; the second Baron von Kaz novel, The Feather Cloak Murders (1936), has a Hawaiian setting and lists as its authors Darwin and Hildegarde Teilhet. Later Teilhet books might be attributed to either or both Teilhets, but with one or two exceptions they were collaborative efforts.
During World War II, Teilhet was an intelligence officer in Great Britain and the United States. Meanwhile, under his own name he wrote adventure stories, two of which were serialized by The Saturday Evening Post. Under Hildegarde’s name, the Teilhets wrote espionage thrillers. For a short while in the 1940’s, Teilhet taught a journalism course at Stanford and he was a consultant for various film producers. One of his nonmystery novels, My True Love (1945), was filmed by Universal in 1952 as No Room for the Groom. During the 1950’s, he concentrated on historical novels; The Mission of Jeffery Tolamy (1951) is a historical espionage story. Teilhet’s final book, completed shortly before his death in 1964, was The Big Runaround, a thriller based on industrial spying.