This is the list of named characters on 24 who appeared in only one episode of the show. This list includes those who were heard once over live audio (e.g. Alan Optican), seen once in live tele-conferencing footage (e.g. Steve Hillenburg), or appeared once as a corpse. Appearances in recaps, deleted scenes, pre-recorded content (including non-live news footage and answering-machine audio), and photographs do not count. Any character who is also cannot be included here. For characters who appeared more than once, see Recurring characters.