Dani (Florence Pugh) and Christian (Jack Reynor) are a young American couple with a relationship on the brink of falling apart. But after a family tragedy keeps them together, a grieving Dani invites herself to join Christian and his friends on a trip to a once-in-a-lifetime midsummer festival in a remote Swedish village. What begins as a carefree summer holiday in a land of eternal sunlight takes a sinister turn when the insular villagers invite their guests to partake in festivities that render the pastoral paradise increasingly unnerving and viscerally disturbing.