Luke, Connor, Thea and Violet spend their first holiday together alone in their father's house in France. The boys don't really know him -- he left their mother when she was still pregnant with Connor, getting together with the girls' mother soon afterwards -- and they don't really know their half-sisters, either. Luke, the eldest and most easy going of the four, is keen to bring a new shape to their overlapping, unconventional family; Connor and Thea, born just six months apart but a world of difference between them, are attracted to each other, something they try not to acknowledge but which keeps pushing its way to the surface; Violet, the youngest, is trying to figure some things out about herself and trying desperately to forget others. Sex, in its multiple pleasurable divergences and forms, disturbances and abuses, is on the minds of all of the siblings during the hot, lethargic summer days next to the pool. Meanwhile the land is responding and reacting to something inexplicable and eerie. There is a sound, a strong buzzing tonal undercurrent that only Connor can hear, and when Violet one night sees a plane light abruptly drop and disappear in the night sky, it signals the unsettling beginning of something that threatens so much more than their turbulent holiday.