Revealing Coworker's Startled Reaction

What happens here

Following the abrupt closing, the portable toilet door is quickly pulled back open. A female coworker, wearing sunglasses, is then revealed as she exits the portable toilet. She lets out a very loud, high-pitched scream of surprise, placing her hand on her chest in a clear display of being startled. This reaction is the core of the prank and has no connection to the task of thoroughly cleaning and sanitizing a toilet base or floor area.

Goal: Immediately after closing, the portable toilet door is reopened, revealing a coworker who reacts with a loud scream of surprise and visible shock.