Cuoco plays a flight attendant in a new mystery series, aptly titled The Flight Attendant, which airs on HBO Max.
Speaking to USA Today, Cuoco said that “out of nowhere” a flight attendant “came up and went, ‘Penny, Penny’,” before she “started knocking” in her direction.
Cuoco had no idea what the flight attendant was doing until later, when she realised she had been imitating the habit of Jim Parsons’ Sheldon Cooper.
“I know the flight attendant thought this was very funny and in hindsight, maybe she now regrets it,” the actor said.