On a quiet afternoon in a wine bar, Damian Briggs tries to drown his thoughts in wine.

But as the world around him fades into black and white, a stranger suddenly sits before him, speaking like his own conscience. In a sequence of memories, conversations, and silent images, Damian is drawn back to the last years with his wife, Sabrina: from the warm, carefree moments of their love to the days when illness and pain darken their everyday lives. Sabrina has decided to choose the Soluna program, a legal assisted suicide option in Switzerland. Damian desperately fights against this decision, searching for healing, for hope, and at the same time wrestling with his own fear of losing her. The man in the suit confronts him with an uncomfortable truth: love sometimes means letting the other person go.

Between past and present, between color and monochrome, Damian must accept that the day moon not only heralds the end of a day, but also the courage to find light in the darkness.