"Dear Zachary" is a heart-breaking Slamdance documentary by Kurt Kuenne, shown at left playing the keyboard with his friend Andrew Bagby when they were children.

Bagby was murdered at the age of 28. The prime suspect was his ex-girlfriend, who was pregnant with Andrew's child, later named Zachary.

Kuenne conceived the documentary initially as a way for Zachary to learn about his father, because Kurt had many home movies featuring Andrew. To reveal anything more about the story would ruin it. See what happens at the last screening on Thursday.

Kurt told The Salt Lake Tribune that he had long dreamed of going to the first public showing of the doc at Slamdance last Saturday. He did go, but unfortunately, he was sick as a dog after being so stressed out over editing the final cut.

"I basically was a staff of one," Kurt said. "My immune system was at its most vulnerable state, and then I came to this freezing place."