The Twilight Zone (1985)

The smartest boy in school is a target for bullies. At home in bed after an attack, the boy meets the "Shadow Man" under his bed who offers him a solution. The "Shadow Man" is a serial killer, but tells the boy that it never kills the one underneath whose bed he lurks. In defiance of all the curfews, the boy goes out and taunts the killer to show his courage. As the other kids run, the boy stands confident as the "Shadow Man" approaches, only to be told, "I'm not the Shadow Man under your bed."