the first episode of the subsequent story, "the space museum", begins with a brief clip of the finale of episode 4, "the warlords", where the time-travellers stand in period costume round the tardis console, literally frozen in time (it is confirmed as a clip rather than a restaged scene by an off-camera cough on the soundtracks to both "the warlords" and "the space museum"). this is the only known surviving footage from the final episode.