In the dead of winter, Elon Musk, electric-vehicle and space-flight entrepreneur, got on a plane at 6 a.m. in Southern California and took off for frigid Detroit.
Mr. Musk, who divides his week between two companies and five young sons, may have been hesitant to make the trip. A few months earlier, Michigan had passed a law blocking his company, Tesla Motors Inc., from selling or even displaying its cars at factory-owned showrooms in the state.
And the forecast low in Detroit was 3 degrees.
Still, he went.
Mr. Musk -- a bona fide icon in Silicon Valley but still an enigma in Detroit -- made his way to the Renaissance Center, home of General Motors, to deliver an important message to his audience about the future, if only they would listen.
"Electric cars are just fundamentally better," Mr. Musk said at the start of an hour-long talk at the Automotive News World Congress. "I think that's where the future is going to go, but it's only going to go there if the big car companies make risky decisions to do electric vehicles. I hope they do, and we're trying to be as helpful as we can be."
Plea for help
Mr. Musk didn't need the publicity.
News outlets hang on his every word about Tesla or his spacecraft company, SpaceX, which holds a contract from NASA to launch cargo into orbit. He is widely credited with inspiring Robert Downey Jr.'s portrayal of entrepreneur Tony Stark in the "Iron Man" films. Even the smallest revelation about Mr. Musk's personal life -- he recently told users of the website Reddit that he sees showering as his most valuable daily habit -- spreads across the Internet like wildfire.
GM CEO Mary Barra said last week that she can often remain anonymous when shopping for groceries. That is rarely true for Mr. Musk. Wherever he goes, people ask to take photos with him.
"If I go try to hang someplace with my friends, people will come up to me quite a lot," said the soft-spoken South African native, before adding: "They're almost always really nice and everything."
And yet, for all his fame and fortune, Mr. Musk desperately needs Detroit's help.
He has bet everything on his vision of electric cars. During the discussion, Mr. Musk described how Tesla sank him into the depths of despair and near bankruptcy, only to stage a comeback. A few years later, Mr. Musk has enough confidence to predict that Tesla's electric car deliveries could increase a hundredfold between now and 2025.
Even after doing that, Tesla would be dwarfed by GM, Toyota or Volkswagen. There are 100 million cars and trucks sold worldwide every year. In 2014, Tesla delivered about one-thirtieth of one percent of them.
That is fine by Mr. Musk. He is not driven by profit or market share. He is not inspired by wealth or racing trophies. Simply put, he wants to end the era of the internal combustion engine that began in Detroit a century ago.
"Most of the good that Tesla will accomplish is by cutting a path through the jungle to show what can be done with electric cars," Mr. Musk said. "The significance we will have is the degree to which we do force other companies to accelerate their plans."
Mr. Musk knows it's not an easy time to see that path. Oil prices have plunged to a 10-year low, halving the price of gasoline for Americans. The drilling technique called hydraulic fracturing, used from Pennsylvania to Texas to North Dakota, has vastly expanded the accessible supply of oil and gas under Earth's surface. By how much is not known.
In such a market, Mr. Musk said, car companies cannot count on the price of fossil fuels to serve as a "forcing function" that drives customers to buy electric cars.
Detroit's titans know this well. Next to speak after Mr. Musk was Sergio Marchionne, CEO of Fiat Chrysler Automobiles, who has openly discouraged people from buying the all-electric Fiat 500e because it's a money loser for his company.
"Every time I sell one, it costs me $14,000," Mr. Marchionne said in Washington last May.
Mr. Musk gave some credit to Nissan, the maker of the all-electric Leaf. He offered mild praise for GM, which treated the Detroit auto show as a coming-out party for the second-generation Chevrolet Volt plug-in hybrid and a concept car dubbed the Chevrolet Bolt that would offer 200 miles on a charge.
"Even if I don't know what I don't know, which is the oil price, there is one trend which is unmistakable," Nissan CEO Carlos Ghosn said at the Detroit auto show last week. "It is emissions regulations are going to become tougher. Global warming is becoming more and more of a threat.
"I think zero-emissions technology, particularly electric cars, is here to stay and here to grow," he added.
In Mr. Musk's eyes, cars such as the Leaf and Bolt do not represent competition. They represent progress.
But if automakers do not move more quickly, Mr. Musk suggested, they will pay the price later, along with the rest of humanity, as carbon emissions from the tailpipes of gasoline cars change Earth's climate and ravage the planet.
He used the analogy of a city that lets its citizens dump their garbage into the street. Eventually, he said, "terrible things" happen.
"I think we're really going to regret the amount of carbon that we're putting in the oceans and atmosphere," Mr. Musk said in his parting words on stage. "We're really going to regret it."
This was the very idea that led Mr. Musk to invest in Tesla in 2004.