Stomach-churning video shows a man letting a large rat loose in a New Jersey McDonald’s — and diners not lovin’ it.

The 42-second footage posted on Facebook last week by the account Fe Bugout shows a man entering the fast food eatery in downtown Newark carrying an overweight white rat in a clear case, trailed by a young boy.

“Let me hold it!” the child begs.

But the man has another idea — and soon lets the critter out of the case.

Chaos swiftly ensues as diners realize the monstrous rodent has been let loose and try to escape.

People can be heard screeching “Oh s–t!” and “What the f–k!” as they nearly trample each other, hopping over tables and chairs, on their way to the back of the eatery or the door.

“Let me out! Let me out!” a man heading for the door can be heard saying. Others can be heard laughing as the clip ends.

The owner of that McDonald’s franchise, Celest Quintana, told NJ101.5 that the dining room was cleaned and sanitized.

“We are currently working with local law enforcement to identify the person responsible for this deliberate act,” Quintana said.