The plot copies ideas from several movies I've seen such as 2008 french movie Vampire Party (Les Dents De La Nuit) - 5 people got invitation cards to a special party off an island and found out they are nothing but walking prey to a bunch of vampires. Another one is Saw, with the video recorder scenes.
For the movie itself, I'm disappointed about the script as it brings nothing new to the table. What makes a story / movie special is the local cultural elements + human nature / universal questions we all have or face during the era. For horror movies, especially Asian, what works most but neglected most are urban legends.
The surprising part of this movie is one of the actress is more famous than anyone in the film turns out to be a Japanese porn actress - Maria Ozawa could land a role more than a sex scene. It's another porn actress got into mainstream movie after Dany Verissimo successfully played a role in Distrct 13 (Banlieue 13).