Spiritwalker may have been an idea that was best left on the shelf. In book form, where there is considerably more scope to explain what is happening and why, this might have worked.

As it stands in a substantially briefer, film form, its just confusing. The character constantly jumps from persona to persona, trying to find his way back to himself. To say this results in an abundance of cognitive dissonance in the poor viewer, is an understatement. You get your bearings with a character before he's suddenly, someone else.

Quality of acting is predictably good, few South Korean films disappoint in this regard. Actions scenes are well done too, no complaints there.

In summary, some concepts work, others don't. For me, at least, this is one of the don'ts......