no more Mr Nice Guy

no more Mr. Nice Guy

An expression indicating that someone is no longer going to behave in a pleasant, tolerant, or carefree manner. OK, no more Mr. Nice Guy. The next person to speak out of turn gets detention.
See also: guy, more, nice

no more Mr Nice Guy

used to suggest that you will stop being lenient and begin to adopt more severe measures.
See also: guy, more, Mr, nice
References in periodicals archive ?
Although he doesn't smoke or drink very often, he says from now on it's no more Mr Nice Guy.