'We're actually all rather terrible.' On the cusp of the 1960s, when fourteen-year-old Ben moves into the ancestral home of his aunt and uncle, he is shocked by their wealth and glamour. Under the watchful eye of the Merryvale Mask, his sophisticated cousins teach him how to appreciate their languid opulence and draw him into the world of the elites. But five years later, when a woman's body is found on the estate, his new life begins to crumble. As the family is placed at the centre of a murder investigation, Ben starts to see their manipulative power in a harsher light. Placed on a collision course with his family, Ben faces a dilemma: how far is he willing to go to fit into their world?