Unlike many of these Taiwanese movies with the word 'ninja' in the title this one actually has a ninja in it(or at least a guy with a very ninja-like outfit on), so that's something. It's also a pretty decent blend of action/kung-fu and for about the first half of the runtime it's a crime drama before morphing into your more standard kung-fu flick. There's quite a bit of variety on display besides your standard fist and foot-fighting you get gun-fu, motorcycle-fu, Frankenstein-fu, skiing-fu and even some unexpected rollerskating-ninja-fu. Muzak versions of Procol Harum's 'Whiter Shade of Pale' and 10CC's "Not in Love" play on the soundtrack which are not songs I would ever pick to be in an action-packed film, but what do I know? AKA NINJA AND THE THIEF and TO CATCH A THIEF. The director on this is credited as Tommy Lee but I'm pretty sure it's not the drummer of Motley Crue.
This was recut by the specialist of re-cutting and splicing cheap crappy things together, Mr. Godfrey Ho, and released the same year as NINJA THUNDERBOLT. This version is pretty similar except that you get some additional scenes of Richard Harrison to give it more appeal to those American round-eyes.