The Mongolian Death Worm, based on the creature from Mongolian mythology, is a villain in the TV show Lost Tapes, appearing in the Season 1 episode Death Worm. It is featured as the main monster. In the episode, Benton and his arrogant friend named Gregory compete in a 500 mile motorcycle race across the inhospitable Gobi Desert where they will seemingly impress Benton's wife Lisa, if they win. Gregory messes about with Benton and tells him that he will definitely lose the race. Greg also suggests that if he, Greg, wins, they go to Mount Everest next year (a possible in-joke as one of the later episodes is about the Yeti).
Gregory soon gets lost, but due to his pride and arrogance he cannot back down and the men are left stranded for the night. So, they settle down, and wait until morning when things will be easier to track. They joke a bit before Benton suddenly sees something burrowing in the sand, rather like a worm, and catches it on film. Later, when they are settling back down, Gregory is bitten by the bloodthirsty death worm, and Benton senses an electrical discharge, which catches them both by surprise.
It is at this point the origins of the death worm are theorized by the scientists in the documentary, who debate whether it was a natural species (based on ancient Gobi legends) or whether it was a mutated species (based on the atomic bomb fallouts in the Gobi in the 1940s).
So, Gregory wakes up paralyzed and screaming in pain in the night, and says he can't walk. Benton promises he will go and get help, and gets lost in the dark, but, hearing Gregory's cries when the worm returns to drag him into the sand, Benton goes back to find Gregory, but he was nowhere to be found and seen. He apologizes to Lisa on camera and says his name, and what was happening. Then five more death worms come and drag him off, firing electricity to stun him and he is never seen or heard from again.