The Sleepwalkers by Scarlett Thomas

Still reeling from the chaos of their wedding, Evelyn and Richard arrive on an idyllic Greek island for their honeymoon. It’s the end of the season and out at sea a storm is brewing.

They check in to an exclusive hotel, the Villa Rosa, where the proprietor Isabella — a strangely intense woman of indeterminate accent — flirts outrageously with Richard while treating Evelyn with a rudeness bordering on contempt. Isabella tells them the story of 'the sleepwalkers': a couple who stayed at the hotel the year before and drowned in a tragic and unexplained accident. It starts to feel like the entire island is obsessed with 'the sleepwalkers', but what at first seems like a fun tale to tell before bed quickly evolves into a living nightmare. 

Caught in a web of deception and intrigue, where nothing and nobody are quite what they seem, Evelyn and Richard discover that their island paradise may in fact be hell on earth and that their only means of escape is to confront dark truths about themselves and those they love.