To counter the threat from a Soviet "blue water" navy, a large investment was made in the years from 1945 until the 1960s to develop maritime patrol aircraft. For years the Air Staff and the ministries argued over what type should replace the Shackleton, including variants of the Vulcan, the Britannia, VC10 and Trident, before one man strode into the MoD building in 1964, settling the argument with what became Nimrod. To seek and destroy Soviet submarines, Shackletons and Nimrods carried many advanced weapons and sensors, but also played a role in saving lives at sea. Then, after forty years'' service, the Nimrods were withdrawn without replacement after one of the most expensive procurement disasters. Chris Gibson examines the post-war genesis of the RAF''s maritime patrol aircraft, a process that led to Nimrod. From the last flying boats, attempts to improve then replace the Shackleton and ultimately the Nimrod itself, Gibson provides a fascinating insight into the aircraft, weapons and sensors developed to counter the Soviet submarine threat