British thriller in which a carefree holiday in Spain for three young women turns into a living nightmare. Things begin to go awry when Kim (Jaime Winstone), Tammi (Nichola Burley) and Lisa (Sian Breckin) meet three young men and, after joining them for a private party on their yacht, one of the men, Josh (Julian Morris), performs a dangerous anal sex manoeuvre known as a 'donkey punch' on one of the women, accidentally breaking her neck in the process. To avoid getting in trouble with the police, the other five decide to throw the body overboard. Pretty soon, however, guilt and fear get the better of the group, leading to a vicious fight for survival.