Grace (Diana Glenn), her boyfriend Adam (Andy Rodoreda) and younger sister Lee (Maeve Dermody) decide to take a river tour whilst holidaying in Northern Australia. As they drift into a mangrove swamp their boat is suddenly capsized and their tour guide Jim (Ben Oxenbould) disappears. Realising they’ve been attacked by a crocodile, Adam drags Grace to the safety of a tree whilst Lee clings on top of the overturned boat. Adam and Grace frantically try to manoeuvre Lee and the boat to the tree but it is firmly stuck. Stranded in the flooded mangrove swamp, the three holiday makers must work out what to do to survive.