Set during the sweltering Australian summer of 1986, Penny Lane and her best friends Toni and Amy are celebrating Penny's university acceptance with a debauched 'no dick event' at a remote beach house. But the night spirals into chaos when Penny's volatile cousin Kat arrives uninvited, spiked cupcake in hand and a cruel agenda in tow. Things turn deadly with the arrival of Kat's seedy boyfriend Angus and his crew - Rodowsky and the menacing Merrick. What begins as a night of celebration unravels into a brutal fight for survival.