Some reasons why this film is really bad...

For example:

1. The acting performance of Gabrielle Anwar was extremely poor. It is nothing, zero. She always seemed to be thinking: "What am I doing in this cr*p??"

2. The Brazilian natives looked really ridiculous! Actually they were everyday American guys, with some brown paint on their skin :-)

3. The special effects were so weak, even with your highest imagination you were just unable to believe that those scenes are really happening...