Amazon Quest.

Thomas Dekker is a diamond cutter attempting to reclaim his right to a portion of a rubber empire in the early part of the twentieth century. Tom travels to Brazil to uncover the fate of his father and along the way meets Teresa, a local girl who offers to be his guide in the jungle. Eventually, they encounter three armed men who take them to Lobato, a bandit who knew his father. Once convinced that Tom is his friend's son, Lobato tells him a lengthy story which culminates with his meeting Tom's father, who rescued him from drowning. With the help of "flashbacks" from an obscure South American feature, Tom learns what really became of his father.