Madrid in the eighties, and Barcelona ten years later. In these two vibrant locales, Castaways follows the relationship between Alejandra and Julio against the backdrop of these poetic urban spaces where dreams, love, and uncertainty intertwine. Drawn to one another but constantly pushed or pulled in different directions by work, family, and life, Alejandra and Julio circle in and out of each other's lives, while first denying and then coming to accept the fact that by the time they are ready to love one another, the chance has already passed.