'Behind Mansion Walls': Bodyguard Confesses 40 Years Later To Killing His Millionaire Boss (VIDEO)

It's been 42 years since the murder of E.C. Mullendore III, and the case still baffles authorities. The story unfolded through re-enactments on "Behind Mansion Walls" (Thu., 9 p.m. ET on ID). Mullendore was beaten until his skull caved in and shot, but who did the heinous deed?

His bodyguard, Chub, was the only person with him at the time of his death and he claimed intruders shot both him and his boss before running off. Four decades later, when Chub was ill, he confessed a different story to an investigator who'd worked the case back in the 1970s.

This time Chub said there was a brutal fight between him and Mullendore that night, and that there was a third person in the house. "If he hadn’t ended it, he knew he was going to be looking over his shoulder for the rest of his life," the investigator explained. The third person shot Chub to corroborate the fiction.

Chub died in 2010, leaving many questions unanswered and the identity of the alleged third person unknown. The murder remains an open case because Chub did not confess to police, but no one has ever been arrested for the crime.

Watch true crime mysteries unfold "Behind Mansion Walls" every Thursday at 9 p.m. ET on ID.

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