Yamato!

Space Battleship Yamato is a popular Japanese franchise that has had as about a complex history / continuity as one could imagine.  First an animated TV series, followed by an animated TV movie which killed off just about the entire cast, followed by a remake of that movie in animated series form minus the killing off of everyone, followed by various other TV movies, TV series, theatrically released re-edits of episodes, a live action science fiction spectacular which adapted the original series and included elements of the second one, and now a new animated series (which again retells the original story).   All that is not to mention the English-language dub / re-edit of the series which played in America when I was a kid under the name Star Blazers.