A large country mansion. A locked room. A gruesome murder. Russian oligarch Alexander Volkov has invited 1000 guests to a party at his palatial Surrey residence, Westgrave Hall. But while giving a private tour of the library, a gunman kills Volkov, wounding his ex-wife and slaying her new beau. Nothing makes sense to DCI Craig Gillard. In the blood-spattered crime scene there are no forensic traces of anyone else involved, CCTV...