Into the Water by Paula Hawkins

When single mother Nel Abbott is found dead in the river running through the town of Beckford, her death brings long-buried secrets to the surface. Earlier that summer, a teenage girl died in the same stretch of water.

Nel's estranged sister, Jules, returns to care for Nel's daughter and confront the past she tried to leave behind. But as questions grow around the deaths, it becomes clear that the town has plenty to hide.

Into the Water is a psychological thriller from the bestselling author of The Girl on the Train, exploring family secrets, unreliable memories and the dark side of a close-knit community.