A new Unsolved Mysteries theory suggests that Xavier Dupont de Ligonnès is still alive. In April 2011, the French aristocrat allegedly murdered his wife and four children before taking his own life weeks later. The story was covered on the Netflix docuseries in the episode "House of Terror." Now, some Netflix streamers believe that the Unsolved Mysteries episode contains a key piece of evidence that has been overlooked.

Unsolved Mysteries reveals that Xavier was proud of his Noble heritage and tried to honor his familial legacy. However, the Netflix docuseries implies that Xavier ultimately gave up on everybody, and everything, after realizing that he didn't have the finances to sustain his family's lifestyle and public image. Interviewees discuss the subject's failed business ventures and his erratic behavior after the death of his father, just months before he allegedly did the unthinkable by murdering his family and thus ending the Ligonnès bloodline. "House of Terror" on Netflix has gained attention because of the bizarre crime scene details, as Xavier's wife, daughter, and three sons were found buried in the family garden (along with the family dogs). Unsolved Mysteries documents Xavier's subsequent disappearance and the trail he left behind before disappearing for good.

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A popular Unsolved Mysteries theory involves statements that Xavier allegedly made before disappearing. On April 11, 2004, relatives received a letter in which Xavier claimed that he'd been working for the United States Drug Enforcement Agency, and that he and his family would have to enter the Witness Protection Program. The letter has never been scientifically linked to Xavier, however it does include specific instructions about how family members should proceed moving forward, and that their official story should be that Xavier and his family moved to Australia. In addition, a school that Xavier's children attended also received a letter that announced the family's move to Australia due to "urgent professional changes." If the letters are indeed authentic and contain true information, then the bodies found under the Ligonnès home are the real unsolved mystery.

Unsolved Mysteries Dupont family

The DEA theory is supported by the questionable nature of the official investigation. A Reddit user cites the hasty cremation of the discovered remains, and notes that multiple people claimed to have seen Xavier's wife, Agnès, in the days after she had allegedly been killed. In addition, the victims were reportedly never identified by DNA, prompting family members to speculate about the official findings. Because authorities failed to properly ID the bodies, there's reason to believe that the cover-up plan somehow connects to Xavier's Witness Protection narrative. Meaning, if the Ligonnès family was declared dead, then people wouldn't spend time looking for them. It's worth noting that the aforementioned Reddit user believes that Xavier did indeed kill his family, but acknowledges the various bits of information that fuel conspiracy theories.

As seen in Unsolved Mysteries, Xavier traveled throughout Southern France after allegedly killing his family, which has been described as a "pilgrimage," or a farewell tour of locations that he had previously visited. Xavier was last seen on April 14, 2004 in Roquebrune-sur-Argens, where he was spotted looking directly into a surveillance camera while carrying a large bag. Some have alleged that Xavier took his own life out of shame, and some Unsolved Mysteries interviewees believe that his "pilgrimage" was merely a goodbye to France, and that he escaped to another country.

Even though the DEA/Witness Protection theory may be intriguing, it's unlikely that government agents would allow Xavier to travel through France while using his personal credit card. Then again, one could argue that the Ligonnès family was given one final private vacation in their native country before taking on new identities elsewhere. Terry Meurer, the Unsolved Mysteries showrunner for Netflix, recently stated that the show received a tip that Ligonnès was spotted in Chicago after "House of Terror" premiered. Although the information has yet to be verified, it does suggest the possibility that Xavier is still out there somewhere, waiting to be discovered.

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