Captain Mannering, until recently employed on the Indian frontier, had returned to Britain after twelve years. Seeking shelter from a storm while on a hike across the Yorkshire dales, he discovers the body of an eminent scientist in an isolated cottage. He finds himself caught up in a case of murder and international intrigue assisted by a beautiful lecturer in technology, the famous pair of detectives, Winter and Furneaux, and the Fox Terrier Tags, as he tries to prevent a secret formula from falling into the hands of both German and Bolshevik agents. Also published as What Would You Have Done?, follow his adventures in Louis Tracy's thrilling mystery... The Sandling Case!