New Tribes Mission has a video in three clips (now available on YouTube).
Basically it's a short reenactment of what happened with some of their missionaries in Papua New Guinea. Their strategy for reaching this tribe was to learn the language and culture, and then start from the very beginning of the bible and teach biblical story lessons that would lay a foundation for leading to faith in Christ. It was 3 months of teaching everyday before they even got to the person of Christ. I was really encouraged by the video. It takes about 25 minutes to watch all 3 clips. If you start, make sure you make it all the way to the end. That's when it gets really good.
Just fyi, D.A. Carson had some sermons on evangelism and missions that were really good, where he mentions this very thing, the importance of laying a foundation before getting to the gospel with those who are biblically illiterate. I believe he mainly stress this point in sermons 3 and 4 of the five part series found here.
Here are the video clips.
Thanks to the believers at Christ Fellowship Hannibal for pointing this out to me.