Reel No 21 comes as an additional reflection on a collection of twenty films in 16mm format, safeguarded in Tokyo by the movement of Japanese solidarity with Palestine. It is an undelivered love letter, written by a Japanese activist, that was lost on its way to a Palestinian filmmaker. Fragments of the letter are found thoughout the collection and compiled into an imagined structure that reveals itself over the course of the film. The film as catalogue, the film as time machine, the film as archive: these themes Reel No 21 deals with have the feel of a montage essay; at the same time, the act of restoring these films exposes the motives, aspirations and disappearances of a generation and its struggles— not only in Japan but also around the world. It is a film essay that explores questions of transnational solidarity by gazing at 16 mm films that have been collected and projected by a Japanese solidarity group