John Kassir is an American actor and comedian. He is known for his work as the voice of the Cryptkeeper in HBO's Tales from the Crypt franchise. He is also known for his role as Ralph in the off-Broadway show Reefer Madness and its 2005 film adaptation. He is also the current voice of Scrooge McDuck since 2016, after the death of Alan Young. Description above from the Wikipedia article John Kassir, licensed under CC-BY-SA, full list of contributors on Wikipedia.
In order to power the city, monsters have to scare children so that they scream. However, the children are toxic to the monsters, and after a child gets through, two monsters realize things may not be what they think.