When Psycho Killer Thinks He Can Lie His Way Out of Murder

When Psycho Killer Thinks He Can Lie His Way Out of Murder

In today’s true crime documentary, we revisit the chilling 2012 murder of 19-year-old Lizzi Marriott in Dover, New Hampshire. A bright and compassionate college student, Lizzi was lured under false pretenses by 19-year-old Kathryn McDonough—someone she considered a friend—and led straight into a deadly trap set by Kathryn’s older boyfriend, 31-year-old Seth Mazzaglia.
What followed was a horrifying sequence of manipulation, coercion, and violence. Lizzi was brutally strangled and sexually assaulted before her body was disposed of in the waters near Portsmouth. Despite Seth’s conviction and a life sentence without parole, Lizzi’s remains have never been recovered, leaving her family without closure.
The case gripped the nation not just because of the brutality, but because of the shocking betrayal by someone Lizzi trusted. As the investigation unfolded, it revealed a deeply disturbing relationship dynamic between Seth and Kathryn—one fueled by obsession, control, and emotional domination. The chilling confession, disturbing court testimony, and the couple's twisted psychology continue to haunt all those who followed the case.


Stay tuned to our channel to uncover the full story. Also don’t forget to like and subscribe to the channel to be one of the first to uncover cases like this from around the world


Featuring real interrogation footage, suspect psychology analysis, and an inside look at how the truth was finally extracted.
Subscribe now for more true crime cases that expose the darkest corners of the human mind.
For educational purposes. Based on public records and verified case files.

---------------------------------------------------------------------------------------------------------------------------

When Psycho Killer Thinks He Can Lie His Way Out of Murder
------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note for YouTube's review team, here is the context of the video: this is an educational documentary and authoritative news piece based on actual police documents and case files. Our goal is to educate the public, inform our audience, and raise awareness..


#truecrimedocumentary #realinterrogatiom #ewu #criminalpsychology #nyc

Copyright Disclaimer
Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, commenting, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statutes that might otherwise be infringing.
Non-profit, educational, or personal use tips the balance in favor of fair use.

When Psycho Killer Thinks He Can Lie His Way Out of Murder