i pick this one up a a blind rental and wasn not really expect much from it . i would never hear anything about it and and like most blind rental and expect it to be very mediocre at best i have to admit that i be very pleasantly surprise . the story center around a group of kid at a high class board school . the school be go on a field trip and and anyone that doesn not want to go have to go back home for the duration of the trip . a group of four student be look for a way out and and with the help of another student and hole up ( so to speak . ) in an abandoned bunker . it all start off a fun and game and until no one come back to retrieve them . with the bunker lock from the outside and the group have no way out and and the tension build a supply run out and the fun come to an end . i think this film be pretty dead on in every sense . the casting and act be great and the transition within the bunker from a fun party place to a death trap be palpable and and the story have some pretty inventive twist that i do not see come . i highly recommend this one for horror or thriller fan who want something a little different from the average slasher or zombie or alien or serial killer and etc . type of film . 8 . 5/10 .