The story is: five women sign up for this secret yoga class which promises eternal youthful beauty to the one of them that does the best. The plot is: there are rules they must follow, some of them break the rules and they get killed. The character development is: make one a yuppie who is being pushed out of her job by a younger yuppier girl; one an attention whore bitch; one a previously fat person who still has crazy cravings; one a goofy twit for an attempt at comic relief; and one completely without personality. Then make the rules they must abide by fit perfectly to each of their weakness, like no mirrors, no contact with the outside world, no unauthorized food ... you get the screenplay 101 picture.
The castle is beautiful, the women are mostly good looking, and some of the kills are bloody enough, but it is not possible to care about anything that happens in the film because the characters are unpleasant cliches and their projects and concerns not worthwhile.
Starring: Eugene, Cha Su-Yeon, Park Han-Byeol, Jo Eun-ji, Lee Young-Jin, Kim Hye-Na, Hwang Seung-Eon