Bretherton: Khaki or Field Grey? is a novel by W. F. Morris, first published in 1929 by Geoffrey Bles. It was published in the U.S. under the titles G. B.: A Story of the Great War (Dodd, Mead & Co.) and G. B.: The Mystery of the Shelled Chateau (Grosset & Dunlap). At the time of its publication, it was called "the finest English war-novel yet issued" by Arnold Bennett. The title of the novel refers to the colours of the uniforms of the British and German armies, khaki and feldgrau.