"The First Fifteen Lives of Harry August" by Claire North.

The novel, published in 2014, is a science fiction and speculative fiction work that follows the extraordinary life of Harry August, who, upon death, is reborn at the same point in time with the memories of his previous lives intact. As Harry navigates through multiple lifetimes, he discovers a secret society of individuals with the same ability. The novel explores the consequences of this cyclic existence, delving into themes of morality, the impact of personal choices on history, and the complex dynamics of knowledge and power. With a unique narrative that spans different time periods, the book offers a captivating and thought-provoking exploration of the implications of living multiple lives.