Dear Zachary: A Letter to a Son About His Father
(2008)

A very moving documentary.
This pooper doesn't give it justice, as it is filled with the testimonies of those involved.

At the beginning of the documentary, we learn the movie is supposed to show Zachary who his father, Andrew, really was. Andrew was murdered by his former lover Shirley, who gave birth to Zachary after killing Andrew.

During the creation of this documentary, Shirley (after being let out on bail and never extradited back to the United States) kills her son Zachary in a murder-suicide. After contemplating suicide themselves, Andrew's parents become child care activists and instigate an investigation, where it is proven the Canadian government should not have released Shirley and should not have put Zachary in her custody.

Andrew's father writes a book about his cause, which becomes a best seller.

Thanks Casey!