long con
[ lawng kon, long ]
/ ˈlɔŋ ˈkɒn, ˈlɒŋ /
noun Slang.
an elaborate confidence game that develops in several stages over an extended period of time wherein the con man or swindler gains the victim’s trust, often bypassing small profits with the goal of reaping a much larger payout in the final maneuver: The key to pulling off a long con is giving your marks the illusion of control while you and your team manipulate their choices.