When a Subway customer asked for extra spinach in his sandwich, he probably wasn't expecting a nasty surprise to go with.
But when Matt Jones' friend opened his up he discovered an entire mouse.
Matt, from Oregon in the US, later posted a snap of the rodent sandwich on Facebook.
He captioned it with: "Look at that Beast of a mouse in the spinach at Subway today!
"Good thing we didn't bite into it! AMAZING! WTF!!! The manager was in shock!"
Matt added: "It was the funniest thing I've ever seen, but also the most disgusting. I laughed because I was like, no way did this just happen."
In a statement, Subway said the restaurant was thoroughly cleaned and the customer given a refund.