When one of Lennox's former colleagues is attacked, Lennox and Drummond quickly realise that all is not as it seems as they become embroiled in a case about vengeance, identity and social justice. The attack is linked to a gruesome attempted murder on a high-ranking establishment figure at a posh hotel which has been hushed up from the police. As Lennox investigates via Edinburgh's saunas, crack dens and poshest hotels, he finds doors slammed in his face; there is an Establishment cover up at play.It's not until the killer targets one of Lennox's own team that the pieces start to fall into place. Tracing the motivation back to an unsavoury incident 30 years ago, Lennox begins to realise that there is more to this case than meets the eye and the killer he has been chasing may not be the driving force behind these murders after all.