Unfortunately, Zhang Yimou has fallen to the seductions of CGI and gratuitous slow motion shots. House of the Flying Daggers (Shi Mian Mai Fu) starts out okay, but gets sluggish in the second half and dies a slow tortuous death from ludicrous setpieces, excruciating melodrama and uninspired fight scenes. Everyone struggles with the pseudo-classical Mandarin lines, and there's little chemistry between any of the three leads. The plot borrows heavily from Infernal Affairs (Wu Jian Dao) -- in fact House might as well be titled Infernal Affairs: Tang Dynasty instead. Heck, it's even got Andy "Wo Shi Jing Cha" Lau in it.
The only things going for the movie are Zhang Ziyi's acting, Kaneshiro's impishness, the beautiful landscapes and Emi Wada's lusciously reimagined period costumes. And yes, there are a few gems -- the bamboo forest sequence is actually rather cool to watch. The CGI is fun at first, but tires extremely quickly. You will want to throw a few daggers yourself after watching, for the umpteenth time, close-ups of a CG-rendered dagger as it flies. The gratuitous slow-mo makes the film even worse.
In all, don't believe the hype (incidentally, the guys who came up with the promo displays should be fired -- a crucial plot point is given away in the publicity photos!). There're many good reasons why this film wasn't in competition at Cannes.