A chilly morning mist blankets the Cornish countryside, shrouding the barn in an eerie silence. Inside, a woman lies motionless, her unseeing eyes fixed on the rafters above. A blood-stained note flutters in the breeze. Her death is only the beginning...

Detective Lauren Pengelly and her partner Matt Price are called to investigate a grisly murder outside Penzance. They quickly identify the victim as Carmel Driscoll, a former police officer, and find a cryptic note reading "Ten Green Bottles" next to her body - words from an old English nursery rhyme.

When a second former officer is found murdered with the note "Nine Green Bottles" nearby, Lauren and Matt realise they could be dealing with a serial killer. As they race to uncover the deeper connection between the victims, they discover this quiet part of Cornwall harbours some dark secrets. The key could lie in a decades-old case, thought to have been buried long ago...

With officers' lives on the line and rumoured corruption reaching the highest levels of the police, Lauren doesn't know who to trust. Could the killer be hidden in Lauren's force... maybe even within her team? And can she catch the monster before they strike again, or will she become the final verse in this twisted countdown?

Bestselling author Sally Rigby delivers an unputdownable thriller that will keep you guessing until the very last page. Perfect for fans of LJ Ross, Ann Cleeves and Joy Ellis.