There is a beast inside her, a monster. It wants to scream, it wants to tear things apart. 1816.

Mary, eighteen years old, is staying in a villa on Lake Geneva with her lover Percy Shelley. She is tormented by his infidelities; haunted by the loss of her baby daughter. Then one evening with friends, as storms rage outside and laudanum stirs their imaginations, Lord Byron challenges everyone to write a ghost story, and something fierce and wild awakens in Mary.

Memories surface of the long, strange summer she once spent with a family in Scotland, where she found herself falling in love with the enigmatic Isabella Baxter. She learned tales of mythical beasts, witches and spirits. And she encountered real monsters - both in the rocky wilds, and far, far closer to home...

Illuminating the past like a flash of lightning, this brilliant reimagining of the birth of Frankenstein takes us into a feverish world of waking dreams-where grief mingles with desire, and the veil between beauty and horror grows thin.