Two couples and friends, Ale and Santi and Natalia and Mario, are celebrating their twenty years together by holidaying in the Caribbean. They catch up with each other's news, drink, reconnect... Ale, tipsy on the rum, decides to admit that the night the four met one another, she had played her hand to end up with Santi, who had initially fancied Natalia. The news doesn't get the expected response. The following morning, Ale gets up with a horrible hangover and absolutely no idea of the extent to which she will have to face the consequences of her action.