A ninja who has turned his back on his clan fights to defend an Interpol researcher who is trying to uncover them while seeking revenge upon his erstwhile master.
No-one has the right to complain about the lack of depth or characterisation in a film called “Ninja Assassin”. Essentially it’s a mishmash of ideas that are just an excuse for wildly over the top action sequences in which bad guys are sliced, diced and eviscerated left, right and centre; it has the “gangsters fighting against an invisible assassin” format of the Predator films, the “come with me if you want to live” character dynamic of The Terminator and the soldiers vs aforementioned invisible assassins finale that’s straight out of Aliens. But unlike Doomsday which managed to make a complete hash of its “influences”, Ninja Assassin sticks to what it knows and presents a non-stop frenetic gorefest that’s actually reasonably good fun. The result reminded me of a Wachowski brothers inspired version of Blade that’s a bit thin on plot but makes up for it with above par effects and finely executed action. In fact the bad guys are very much in the vein of The Hand from the Wolverine comics and I would have been a lot happier if the Wolverine film had been handled in a similar way.
Switch your brain to neutral and enjoy.