Inspired by the legend of The Sack Man, the story takes place in a small and isolated town, where a boy needs to pick up his younger brother while his mom is out at work. With the sack man lurking and a missing child, keep his brother safe will not be easy.

In a Brazilian village infested with piranhas, Nanã and Mel are fast growing into adolescence as they dream of ways of protecting themselves against a seemingly inescapable violence. When a mysterious body appears tangled in a fisherman's net, they learn what might be their ultimate protection.