I just saw "The End of the Spear", the true story of how the Wadoni's lives were changed by the message Nate Saint and the other 4 missionaries tried to bring them.  It's an amazingly powerful story of courage, sacrifice, redemption and learning to care for one's enemies.  You can read about it at www.endofthespear.com/.  One of the women, Elizabeth Elliot, who went back to live with the tribe who had killed her husband, has written many good books,(which I love) including "Beyond the Gates of Spendor", which recounts the missionaries' story, in addition to the "End of the Spear "book.  One of the awesome miracles is how Mincayani becomes a grandfather to Steve Saint's kids and they go back to live with the tribe also.  I highly recommend this film and half of the profits will go back to the Indigenous Wadoni people, whose perspective the movie shows. My favorite Jim Elliott quote (but not in the movie) is, "He is no fool to give what he cannot keep, to gain what he cannot lose."