Bruno Mars stopped by ‘Ellen’ the other day, and the two of them had some fun at the expense of a nurse on staff. With Ellen speaking in his ear and telling him what to say, Mars pulls off the prank flawlessly and hilariously.

The setup was the Mars had a sore throat. When a nurse came to check him out, he carried on an awkward and random conversation that included a potato chip getting stuck in his throat, making beeping noises like a truck, and even crying.

The amazing thing is that Mars keeps a straight face throughout the prank, a feat that would not have been easy to do.