Basically, this is the era of sassy girls like Charlene Choi, following the success of My Sassy Girl that propelled Jeon Ji Hyun to international stardom. The next sassy princess would have to be Charlene Choi, who is every essence of sass. Sad to say, her counterpart Gillian Chung belongs to the long gone era of sweet whiny girls of the Vivian Choi and Athena Chu's genre.

Thumbs up for girl power!

Take for example the vampires. When you make a movie that involves something that doesn't exist in real life or is not experienced or seen by most viewers, a filmmaker should be careful to fill in the blanks with rules that govern this particular thing's existence. Vampires in western movies cannot be seen in mirrors, burn in direct sunlight, hate crucifixes, etc. Vampires in Hong Kong films tend to hop instead of walk, Taoist priests are their hunters, they see a person by their breath, etc. The vampires in this movie tend to mix, discard, and create new rules seemingly at their whim. What seems to hold one vampire, later in the movie, may not hold to another. It gets a bit frustrating.

This experience extends to other areas of the film where events occur and you aren't sure how to react. Should I laugh, gasp, smile, cry, or what? It seems a bit forced to me. Like they are trying a little too hard. I think this may stem from this possibly being one big commercial for Emperor Media Group's recording artists. Strangely enough, this movie was made by EMG and starred musical artist that they publish (Jackie Chan, Edison Chan, Ekin Cheng, the Twins, Karen Mok etc.) Hmmmm...

There are good things to say about this film. The cast for one. It was really fun watching Jackie Chan and Karen Mok getting married. Jackie is in this film a bit more than the term "cameo" justifies. I found all of the cast pretty likeable. I even found myself liking the twins of the title, Gillian Chung and Charlene Choi. They are a singing duo (called "Twins" oddly enough) that's hot right now. They're cute but not annoyingly so, and they are actually funny at times. Also, there's some pretty good fight scenes choreographed by Donnie Yen. Some of it relies too much on wirework though.

The movie plot could have gone very far, but it didn't. Watching this movie felt like the HK movie producer decided to just throw on stage a couple of teen idols, tell them to say a few lines and do a few things, just to squeeze a few bucks out of my pockets. I've seen Nicholas Tse in better movies, and Ekin still can't act (with the exceptions of "Legend of Speed 2" & "Storm Riders"). The "Twins" are just way overhyped. The little side story of love in here is just so bland and seemed to be made only for the purpose of adding extra length to the movie, which I might add, could have been fairly short.

If you want a sword-swinging-in-modern-times flick, go with "Princess Blade". "Twins Effect" is just overhyped teen idols milking school girls' money. I'm giving this movie 1 star [out of 5] because for the brief few minutes of this long, long boring movie, there were nice fight choreography from Donnie Yen.