Being a big fan of the original Captain Harlock TV series from the 70s I looked forward to the new breed of Leji Matsumoto's productions. Unfortunetly I was mostly disappointed in the way they treated the well known characters and in the quality of storytelling in general. Cosmo Warrior Zero is one of the very few to be actually true to the orgins and at the same time presenting some fresh, interesting ideas.
For Harlock fans the very premise is a treat already. We follow Captain Warrius Zero who is a sworn enemy of Captain Harlock and promises to give everything he's got to hunt down the legendary pirate. The conflict is grounded in the different ways the two men perceive where their honour and duties lie, so it won't be settled just by the revelation they both have good intentions and qualities they respect a lot.
Another point of interest are the interactions between human and mechanized crew memebers of Zero's ship. Humans and the Mechanized Empire just finished a bloody war resulting in a difficult peace treaty and a promise of "cooperation". Both sides have naturally a lot of ill feelings towards each other and it's up to Zero, who lost his closest family in the war, to be above any destructive sentiments and make everyone work seamlessly together. In the first half of the series the moral dilemmas are pretty overwhelming, even for true men (in Matsumoto sense of the expression).
Unfortunetly the story becomes a complete mess after the eighth episode. It feels like a big part is missing there. The specials seem to me to actually fit into this void between episodes 8 and 9 and not after the whole series run as suggested everywhere. However, even when we assume such chronology there are references to important events in 9 that haven't happened anywhere onscreen. Additionally things develop too quickly in those final episodes and the depth and more subtle moments are lost.
The series has great appearances by Harlock, Tochiro and Emeraldas, showing a lot of their charisma and fascinating personality traits from the good old 70s. The only annoying thing about this incarnation of Harlock are the stupid pyjamas he constantly wears instead of his classic garments. The new characters are very Matsumotoesque in their behaviours and are essential for the various plot points, but with exception of Zero lack that special something that would make them particularly memorable. Well, there is one other character, that I'd care to see again, a cool brutal pirate captain that appears in the specials and one other episode.
A few words on the visuals. The animation is professional, but at the same time definetly low-budget. The done-by-computer colorization is something I personally dislike in modern made for TV anime, but perhaps other people will have no gripes about it. However, I'm sure the poor CG and the sloppily put together opening will be annoying to everyone. The action suffers a bit due to the CG ships cheapness, but the strong concepts behind the battles and their more strategic nature save those scenes. The character designs fully embrace Matsumoto's unique style and are mostly of the highest quality.
In conclusion, Cosmo Warrior Zero is worth trying out for someone who is looking for some worthy Matsumoto treat, even if only in small supply. Just prepere yourself for considerable disappointment with the later episodes, because for whatever reasons the project seems to have fallen apart during production and I'd describe it as incomplete.