“Girls Trip” breakout Tiffany Haddish fights dirty in a new PSA on the importance of hand washing sponsored by the group People Against Dirty.

“I got one question,” Haddish begins. “Do you wash your hands after using the restroom? Well today, we’re going to find out how many people keep it clean when they think no one is watching.”

From there, Haddish sits in an observation room and watches patrons exiting bathroom stalls. Some rinse their hands without adding soap, while others skip the sink completely.

“Excuse me, this is your inner sister girl,” Haddish says to one woman over an intercom. “Could you wash your hands? That’s how you get sick!”

At one point, Haddish takes matters into her own hands and leads by example to show bathroom attendees how to wash their hands.

Even those who do wash their hands are subjected to Haddish’s scrutiny. “What you making — butter, girl?” Haddish says to another woman who uses several pumps of soap.

Haddish then makes a plea to the camera. “Please world, wash your hands. Please. ‘Cause you never know when I’ll be watching. I see you,” she says.

“Who better than Tiffany Haddish to help method fight dirty?” said Doug Piwinski, chief marketing officer of People Against Dirty. “She’s culturally relevant, super funny and one of the most sought-after comedic talents today. One would think that washing your hands after using the restroom is a no brainer, but Tiffany has turned this seemingly simple act into something memorable, impactful and shareable.”