Watch LookMovie. Inspired by the horrific Mann family murders of spring 1988, Garden Valley follows two friends lost in a haze of hard rock, reckless choices, drugs, and volatile romance. Set against the bleak landscape of the Garden Valley trailer park on San Antonio’s Southside, the story unfolds over one fateful day—April 14, 1988—when their lives descend into chaos, obsession, and the lingering psychological shadows of violence.