game is up

the game is up

The plan or scheme has been discovered and/or thwarted; the game, trick, or deception is at an end. The game is up, Smith! The police found your fingerprints all over the safe. We tried to smuggle a kitten into the house, but when mom saw me carrying a saucer of milk, I knew that the game was up.
See also: game, up

game is up

 and jig is up
Fig. The illegal activity has been found out or has come to an end. When the police were waiting for them inside the bank vault, the would-be robbers knew that the game was up. "The jig is up!" said the cop as he grabbed the shoulder of the pickpocket.
See also: game, up