Next in Line by Jeffrey Archer

London, 1988. Royal fever sweeps the nation as Britain falls in love with the ‘people’s princess’.

Which means for Scotland Yard, the focus is on the elite Royalty Protection Command, and its commanding officer. Entrusted with protecting the most famous family on earth, they quite simply have to be the best. A weak link could spell disaster.
Detective Chief Inspector William Warwick and his Scotland Yard squad are sent in to investigate the team. Maverick ex-undercover operative Ross Hogan is charged with a very sensitive—and unique—responsibility. But it soon becomes clear the problems in Royalty Protection are just the beginning. A renegade organization has the security of the country—and the Crown—in its sights. The only question is which target is next in line…