Grace (Diana Glenn) her younger sister Lee (Maeve Dermody) and husband Adam (Andy Rodoreda) are going on the Blackwater Barry tour out in the Mangroves for fishing. After leaving the home of Grace's mother, Lee convinces the three to go to a crocodile exhibit. They learn that local males of that beast can grow to massive sizes and are extremely dangerous. Later that day, the trio go to a bar, where Lee suspects that Grace is pregnant when she refuses to have a drink.