The Switch by Lily Samson

Two couples. One twisted game of love and obsession. A dark domestic thriller about the dangerous secrets that come to light when a wild fantasy turns sinister. . . When young couple Elena and Adam are offered the chance to house-sit in their dream neighborhood for a few months, they jump at the opportunity. The leafy South London enclave is a world away from everything they know, complete with grand homes, lush gardens, and quaint local coffee shops. Soon Elena crosses paths with the beautiful and enigmatic artist Sophia and her husband, Finn, and she and Adam are pulled into their orbit. Sophia is everything Elena isn’t—glamorous, alluring, successful—and Finn exerts a mysterious pull on Elena that she can’t seem to shake. Elena’s infatuation with Finn grows stronger by the day, and when Sophia proposes a thrilling game to her new friend—to swap partners in secret—Elena quickly agrees. It’s not long before Elena experiences a sexual awakening that blossoms into an illicit love affair, but Sophia’s plans are far more dangerous than Elena could ever have imagined. . .