Watch Titan for Free: How to Stream the Movie Online at 123Movies. . A team of young doctors on a humanitarian mission through the Amazon rainforest come to realize that not everyone – or everything – is happy to see them. Their arrival draws the attention of an ancient predator, the “Boiúna”. This ancient killer, dominant on land and water, emerges to reclaim the jungle. The ensuing fight for survival blurs the roles of hunter, prey, and hero.