Max and Annie Kingsley have left the London rat race with their twelve-year-old son to set up a glamping site in the wilds of Cornwall. Eager for a dry run ahead of their opening, they invite three old university friends and their families for a long-needed reunion. But the festivities soon go awry as tensions arise between the children (and subsequently their parents), explosive secrets come to light, and a sudden storm moves in, cutting them off from help as one in the group disappears.