For readers of All the Missing Girls and You Will Know Me, Impossible Causes is a gripping, claustrophobic thriller about isolation, power, and the lies that fester when witnesses stay silent.

For seven months of the year, the remote island of Lark is fogbound, cut off completely from the mainland.

Three strangers arrive before the mists fall: Ben Hailey, a charismatic teacher looking to make his mark, teenager Viola Kendrick, and her mother, both seeking a place to hide from unspeakable tragedy.

As the winter fog sets in, the presence of the newcomers looms large in this tight-knit community. They watch as their women fall under the teacher's spell. And they watch as their daughters draw the mysterious Viola into their circle. The girls begin to meet furtively at night, dancing further and further away from the religious traditions that have held Lark together for generations.

But when a body is found one morning at the girls' meeting place, high up among the sacred stones of Lark, faith turns instantly to suspicion and fear. For the island is weighted with its own dark secrets, and now it is time for them to come into the light.

Eerie and menacing, timely and moving, Impossible Causes is an unputdownable thriller that examines the consequences of silence kept at young women's expense.