In 1973, five men and six women sailed across the Atlantic on a raft. A social experiment and a scientific study of violence, aggression, sex and group behaviour, conducted by a radical Mexican anthropologist. Everything was filmed and documented in a diary. But theory is one thing, the other things is practice. And without wanting to reveal too much, the experiment didn’t exactly go as planned. Over 40 years later, the Swedish director Marcus Lindeen brings the crew together again for the first time since the experiment, on a faithful copy of the raft in a film studio, to look back at the three intense months they spent together, isolated and without privacy, on ‘The Sex Raft’, as the press called it. An experiment that in many ways encapsulates the boundless 1970s, and which produced a strange wealth of analogue ‘big data’ about human relations in the shape of Super 8 footage, statistics and diaries from the journey. Lindeen’s film about the Acali experiment is a both dramatic and psychologically insightful work, which brings a sensational, but almost unknown story into the present age without losing sight of the nuances of the fatal adventure.