When Glee star Cory Monteith was found dead in his Vancouver hotel room at age 31 July 13, 2013, fans were left not only shocked and distraught, but also confused by the swirl of rumors that followed. A new TV special, Autopsy: The Last Hours of Cory Monteith, focuses on his tragic passing, as seen in Us Weekly's exclusive sneak peek.

The REELZ series' Saturday, December 3, episode will examine the timeline of events leading up to Monteith’s death, along with delving into medical evidence. According to Autopsy, the actor — who played quarterback Finn Hudson on the Emmy-winning Fox musical series — was called into a meeting with Glee creator Ryan Murphy March 28, 2013, over substance-abuse concerns.

In the preview clip, a reenactment depicts Monteith as uneasy as he meets with Murphy at Fox Studios in Los Angeles, three and a half months before Monteith’s death. (Monteith and Murphy are both portrayed by actors in the footage.)

The tense scene is accompanied by commentary from media journalist James Desborough. “Cory was late several times to work, and people began sensing from the smell of his breath that there were problems, and there were issues,” Desborough says. “We understand from sources that at times he would neck bottles of whiskey in just under an hour and would then continue drinking until he passed out.”

The show's narrator continues to tell the story of the meeting between Monteith and Murphy. “It’s not only his drinking that Murphy is concerned about; it’s his suspicion that Cory is taking drugs,” the voice-over says. “To Cory’s dismay, Murphy tells him he’s pulling him off the show, despite there being two episodes left to film.”

Us previously reported April 1, 2013, that Monteith was entering rehab for substance addiction. He did not appear in Glee's final two episodes of season 4, as they were filmed while he was seeking treatment, and he died before production began on season 5. (The cause of death was a mixture of heroin and alcohol.)

Watch the preview clip above. Autopsy: The Last Hours of Cory Monteith airs on REELZ Saturday, December 3, at 8 p.m. ET. 

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