The Secrets Behind Mary Winkler's Shocking Crime

The charismatic young preacher Matthew Winkler and his beautiful wife, Mary, met at Bible College. Along with their three young daughters, this picture-perfect couple had the pride and respect of their 200-person congregation of the 4th Street Church of Christ in Selmer, Tenn. The Church of Christ is a religion that believes in the literal interpretation of the Bible — men set the rules in their families, divorce is frowned upon and there is no room for women as church officials.

One summer evening the preacher never arrived for the weekly Wednesday night service. When church officials stopped by his house looking for Matthew, they found him dead, shot in the back with a shotgun blast. Worse still, his wife and three young daughters had vanished without a trace along with the family minivan. A nationwide Amber Alert went out searching for the mother and her daughters, as church officials pondered what demons had visited this man of God and his family.

The answer behind this mystery lie hidden in a web of family secrets, and accusations of financial wrongdoing, violence and sexual secrets that would eventually explode into public view, painting a very different portrait of the relationship between the God-fearing preacher and his wife.

Watch the story Friday on "20/20" at 10 p.m. EDT