1. perfect crime
Wikipedia definition
2. Perfect crimePerfect crime is a colloquial term used in law and fiction to characterize crimes that are undetected, unattributed to a perpetrator, or else unsolved as a kind of technical achievement on the part of the perpetrator. In certain contexts, the concept of perfect crime is limited to just undetected crimes; if an event is ever identified as a crime, some investigators say it cannot be called 'perfect'.
Read “Perfect crime” on English Wikipedia
Read “完全犯罪” on Japanese Wikipedia
Read “Perfect crime” on DBpedia


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