Deep below the hills of the Buckinghamshire countryside, the infamous Hellfire Caves house a pleasure palace for the idle rich – a secret society steeped in satanism, opium and debauchery of the highest order. When the club’s warden, Antony Pennington, is brutally murdered, his bastard sister, Dora, must follow the clues to decode who the killer is, aided by an unexpected ally – ex-Army officer, former opium addict and son of a Viscount, Dr Jacob Sandys. As a shadow dogs their every footstep, Dora and Jacob find themselves in the midst of a shocking conspiracy, caught between the legendary Illuminati and the Hell Fire Club. With time running out, they must fight against both the most influential gentleman of the ton – and the undeniable attraction they feel towards each other…