The film version of national broadcaster NHK’s 2023 drama, “The Voices at War” is the latest in a long procession of domestic films, dramas and documentaries set during World War II. Most are focused on the events that led up to Japan’s surrender, with the atomic bombings topping the list.

Directed by NHK veteran Masae Ichiki, “The Voices at War” not only starts from the war’s early days but also shines a revealing light on a little-filmed aspect of Japan’s war effort: the radio announcers for NHK’s predecessor, Radio Japan, who spearheaded the government’s propaganda and indoctrination push in both Japan and its conquered Asian territories.

Though it is a fictionalized drama, the film uses the real names of the announcers — of whom there are almost too many to keep track — as well as period newsreel footage and photographs.