Hemy neuman children

When Rusty Sneiderman dropped off his son at a preschool in the Atlanta suburb of Dunwoody, Georgia, on Nov.

18, 2010, the morning calm was shattered by the sounds of gunfire.

Sneiderman, 36, lay dead after someone drove up in a silver minivan and fired four shots at close range before fleeing, according to witnesses.

"It was so surreal, the experience, in that there was no chaos or running or yelling or anything.

He just walked back to his van. It didn't look like what I would think a murder would be," witness Chris Lang told "20/20." "And everyone thinks they would know what you'd do. You don't."

A new "20/20" episode, "Fatal Disguise," airing Friday, Nov.

15, at 9 p.m. ET and streaming the next day on Hulu, examines the case.

Witness Larry Minogue, who dropped off his own son at the preschool an hour before the shooting,