This film is just awful. It literally has no redeeming features.
The dialogue is awful. The characters you know and love form the first movie have been turned into rubbish cliches of themselves (ooh, Jonathan's the cheeky one, lets make sure no-one gets to forget he's the funny one by giving him all the funny lines we wrote in our lunch hour) . There is one unintentionally hilarious scene in particular. How do they get around the fact that the main female lead from previous movies isn't reprising her role? lets just get the rest of the cast to pretend it's the same person. It just doesn't work. She doesn't do the character justice or take her in any new directions. Not her fault, just bad script.
Jet Li should have been a selling point, but quite how he can go from something like Hero to this tripe is just a bad career move.
I've only ever walked out of one movie at the cinema and that was Van Helsing. The only reason I didn't leave during this film is that the previous films were so much fun and didn't take themselves too seriously and were well written. I just thought it would get better but it never did. It's for films like this that play should let you have a "no stars" option.
Oh, and the Yeti's look awful.