Batman: The Animated Series - Season 2 Episode 4 -

Wealthy socialite Veronica Vreeland returns from Central America, bringing tiny handmade dolls for all her friends. According to native legend, once placed under a pillow, the dolls do the sleeper's worrying for them. Unknown to Veronica or her guests, each of the dolls was made by the Mad Hatter, and contains a tiny microchip which plants hypnotic suggestions inside the sleepers' brains.