The marketing execs who approve the cover art of these South Korean DVD releases should be shot. Wide Awake (aka The Return) is not a cheap slasher as the cover depicts.
On the contrary, it's a very entertaining thriller with a lead antagonist who suffers from post-traumatic stress disorder after experiencing anesthetic awareness during a childhood surgury. This is chock-full of originality because the killer uses exotic medical tactics to dispatch his victims. The orchestration behind one particular murder is magnificent, going down as an instant classic in cinema. However, the final half hour drops the ball a bit with an unoriginal, cliched climax and a few too many twists that take the already stretched realism and throw it out the window. A better ending would have made this film critic-proof, but in its current state it still packs quite a punch.
Do yourself a favor and see this. It's quality entertainment.