The opening scene of "Hazel Falls," book six of the Old Town mystery series, occurs at the Alexandria water treatment plant in the Eisenhower Valley, where Hazel, a mechanical digging device, tunnels beneath the city to complete a major water remediation project. Operations come to a screeching halt when skeletal remains are unearthed at the site, conjuring up memories of the decades-old tragedy involving the Orr sisters. Eighteen years ago, the sisters had innocently attended a concert. At the end of that evening, both disappeared. One was found dead the following day. The other has never been heard from since the night of her disappearance. The discovery of the human remains occurs just as the convict at the center of the case appears in court to have his sentence reevaluated. Due to the malfeasance of a key witness, the convict's conviction may be overturned. But was he ever guilty of any crime? How do the human remains discovered at Hazel Falls affect his case? Are the human remains those of the missing sister? Who else might bear partial or total responsibility for both the murder and the disappearance of the Orr sisters? The convict is released into the community pending new court proceedings as ghosts from the past gather in the present to influence the reconsideration of the case. Criminal miscues, legal maneuvers, and lost opportunities erupt as past memories collide with present-day revelations to uncover a complex hidden reality. "Hazel Falls" is the sixth mystery in a series that began in 2017 with the release of "Daingerfield Island," featuring Mo Katz. His entourage includes Alexandria policewoman Sherry Stone, research wizard Mai Lin, city prosecutor David Reese, P.I. Curtis Santana, and U.S. Senator Abe Lowenstein. Together, Katz and his group solve a series of murders in the series that also includes "Jones Point," "Slaters Lane," "Roaches Run," and "Gadsby's Corner."