"The Big Secret" by E. Phillips Oppenheim is an exciting thriller book that will take you into a world of intrigue, conspiracies and danger. The main character, a mysterious spy, finds himself in a situation where he has to solve complex mysteries and risk his life to unravel the tangled story. Filled with socio-political content, the book "The Great Secret" will inspire the reader to think about complex questions of morality, friendship and loyalty. This is an exciting read for fans of spy thrillers and lovers of books that will keep you on your toes until the last page.