Watch The Serial Killer's Apprentice online in HD

Dr. Katherine Ramsland interviews Elmer Wayne Henley, the sole survivor of the 1973 Houston Mass Murders, to unravel his chilling journey from manipulated teen to convicted killer — and the terrifying truth behind the line between victim and predator.

The Serial Killer's Apprentice (2025) is a documentary/crime film running 1h 23m. It is available in HD on Cineby for 5 credits. Create an account, add credits and the unlock is yours permanently. Use the player controls for subtitles, quality and fullscreen.

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