leave a/(one's) calling card(redirected from left his calling card)
leave a/(one's) calling card
To leave some item, message, or clue behind, especially at a crime scene, to signify one had been present or involved. It was evident that the string of murders were committed by the same man, as he left his calling card—a single red rose—at the scene of each crime. The cat burglars had started leaving a calling card of sorts, as they used the same method for every heist they pulled off.
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