If you loved Space Pirate Captain Harlock, try Ghost in the Shell: SAC_2045 Sustainable War
A bridge between a film you've already seen and one most people haven't. Ghost in the Shell: SAC_2045 Sustainable War has roughly 14.3× fewer votes than Space Pirate Captain Harlock — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.
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Space Pirate Captain Harlock
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Ghost in the Shell: SAC_2045 Sustainable War
What they share
Both films are directed by Shinji Aramaki, and they sit in Animation / Science Fiction territory. If that's the register that drew you to Space Pirate Captain Harlock, the second film will land in a comparable space — through a different lens.
What Ghost in the Shell: SAC_2045 Sustainable War is
You live in 2045, after economic disaster strikes, but then AI fuels a hidden war, and the series creator leaves you with a haunting vision.