Bjørn (Victor Von Schirach) and Kirstine (Marie Tourell Søderberg) move to the coastal surfing community of Klitmøller ("Cold Hawaii") to settle down and start a family. Their life is upended when Bjørn's charismatic, free-spirited friend Loke (Allan Hyde) arrives. Under the pretext of a modern relationship experiment, Bjørn and Kirstine agree to open their relationship and practice consensual non-monogamy with Loke. However, the arrangement quickly spirals into emotional jealousy, unspoken boundaries being crossed, and secret romantic betrayals between all three parties.