Get ready for an adventure like no other in E. Phillips Oppenheim's Peter Ruff And The Double Four! Join private detective Peter Ruff as he sets out to uncover the truth behind the notorious criminal group known as the Double Four. With danger around every corner, Peter must use all of his skills to outsmart them and bring them to justice. Will he succeed or will the Double Four prove too formidable? Find out in this thrilling novel that will keep you on edge until the very end!