Catch up TV on Knuckle. Watch the latest and all other episodes of Knuckle now online, broadcasted on ABC2. Catch up on your favorite ABC2 TV show: Knuckle. Replay tv on its best! Filmed over a twelve year period, KNUCKLE follows the fighting careers of two Irish brothers as they prove themselves within their community. Vivid, violent and funny, the film gains unique access to this private community.