The Disappearance of Lizzi Marriott

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On the night of October 9, 2012, 19 year old Lizzi Marriott went missing. The University of New Hampshire student had plans to go over her friend and coworker, Kat McDonough's apartment. McDonough shared the apartment with her boyfriend, Seth Mazzaglia in Dover, New Hampshire. In the days that followed, Kat and Seth were questioned by investigators. Although Kat stopped talking to detectives after 2 hours, Seth went on for 11 hours before admitting that Lizzi had died in the apartment. On Saturday, October 13, Seth was charged with Lizzi's murder. He led investigators to Peirce Island in Portsmouth, New Hampshire, where he said he dumped Lizzi's body into the Piscataqua River. The Piscataqua River is known for having some of the strongest currents in the country. It was obvious that Kat McDonough was in an abusive relationship. Two friends showed up at the apartment after Lizzi was murdered and stated that Kat was rocking in the fetal position. She helped Seth dispose of the body. Seth Mazzaglia was sentenced to life imprisonment without the possibility of parole in 2014. Because she testified against Mazzaglia, Kat McDonough only served three years in prison. To this day, Lizzi Marriott's body has never been found.