The world was shocked on October 2, 2017, when news broke that Tom Petty suddenly died at the young age of 66. Now REELZ examines his final hours in Autopsy: The Last Hours of… Tom Petty, airing Sunday, December 13.

One of the world's most eminent forensic pathologists, Dr. Michael Hunter, investigates the circumstances of Petty's mysterious demise. He will examine Petty's autopsy report to piece together why the music legend died so suddenly and unexpectedly.

“So far, I’ve discovered that at the time of his death, Tom was taking a prescription drug for depression as well as a narcotic pain medication called oxycodone, but I don’t think these were the immediate trigger for his cardiac arrest," Hunter explains in Autopsy: The Last Hours of… Tom Petty. "I could see from the autopsy that Tom had a number of physical symptoms of acute stress, including an enlarged heart and damage to his kidneys, likely caused by hypertension. Did the stress of touring finally cause a fatal cardiac event?”

However, before his untimely death, Petty insisted that the stage was his home. “The road and the studio are the only places I’ve ever felt completely OK,” Petty told Rolling Stone a year before he died, explaining why he took on another tour to mark his 40th anniversary with the Heartbreakers.

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As OK! previously reported, the "Free Falling" singer spent a large part of the tour dealing with excruciating pain from a left hip fracture. He thought painkillers would be an easy way to navigate through the tour's last leg, but it wasn't so.

Even when Petty walked off stage on the final night, Skip Coomber, who documented Petty’s last performance, noted "he was limping severely," adding: "That’s when you could tell for the first time that he was in great pain."

On September 25, 2017, Petty played to a packed stadium in Hollywood. He seemed on top of the world, but just one week later, he collapsed at his Malibu home and was rushed to the hospital, where he died the following day.

Petty was said to have overdosed by mixing a variety of medications. After he passed, Petty’s wife, Dana, and daughter, Adria, issued a statement explaining "the pain was simply unbearable and was the cause for his overuse of medication.”

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Now, Dr. Hunter dives deeper in Autopsy: The Last Hours of… Tom Petty, airing Sunday, December 13, at 9 p.m. ET on REELZ.

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