In Greek mythology, Sinon was a Greek warrior during the Trojan War. He pretended to have deserted the Greeks and, as a Trojan captive, told the Trojans that the giant wooden horse the Greeks had left behind was intended as a gift to them. The Trojans were convinced by his solemn oaths, and brought the Trojan Horse into their city (against the advice of Cassandra and Laocoön). Inside the giant wooden horse were Greek soldiers, who, as night fell, disembarked from the horse and opened the city gates, thus sealing the fate of Troy. See Virgil, Aeneid II, 77.

In the Divine Comedy Dante sees Sinon in the eighth circle of Hell where, along with other perjurers, he is condemned to suffer a burning fever for all eternity. William Shakespeare referred to Sinon on several occasions in his work, using him as the very symbol of treachery.