The assignment is enormous, a peculiar mix of duties, some stated and others not, for a man who by all accounts had been leading a comfortable life as a bankruptcy lawyer. His new job? Urban planner, numbers cruncher, city spokesman, negotiator, politician, good cop, bad cop.

The job could not be more politically fraught. Mr. Orr’s harshest critics call him a “dictator” (his authority trumps that of the city’s elected leaders), an “Uncle Tom” (he is black and was sent to run this mostly black city by a white governor) and a “pension killer” (he has said the city can no longer afford the pensions it promised retirees). But Mr. Orr, who was a partner at the law firm Jones Day until his wife and a mentor helped talk him into taking the Detroit job, seems unfazed by the storm around him. He is full of smiles and quips, coolly pressing on.

“If we don’t do something to address the unfunded liability that we have, the 700,000 residents — some of them schoolchildren, some of them sort of skinny, dorky kids like I was, who got beaten up every day at the bus stop by the toughs, who have to walk home in the dark — don’t they deserve better services?” said Mr. Orr, who grew up in Florida and visited Detroit as a youth. “There has to be some balance here. This is our chance.”

This year, with Detroit’s financial troubles becoming desperately apparent, Gov. Rick Snyder, a Republican, called on Mr. Orr, who had worked on Chrysler’s bankruptcy and at the Resolution Trust Corporation, to be sent as an emergency manager with sweeping powers.

At first, Mr. Orr said, he resisted. The salary, $275,000 a year, from the state, would be a pay cut. His wife, who is a physician, would be caring for their two children, 6 and 7, at home in Chevy Chase, Md., when he was in Detroit. And the circumstances were certain to be volatile in a city that was hardly asking for an outsider to step in. Ultimately, Mr. Orr said, he became convinced that it was a call to action.