On April 28th, 1967, Muhammad Ali stood in a line of 46 men on the third floor of a Houston induction center while Lieutenant Steven Dunkley read the rule: take one step forward when your name is called, and the step itself puts you in the Army. The heavyweight champion of the world had spent the morning taking the physical and turning down a ham sandwich. Officers called his name 3 times, warned him that refusing meant a felony, 5 years, and $10,000, and got a written statement instead.

The step would have cost him almost nothing. The government had offered his lawyers "all kinds of deals," no combat and no rifle, just boxing exhibitions for the troops, the same arrangement Joe Louis had in World War II. Sugar Ray Robinson begged him to take it. Elijah Muhammad forbade it, and the last man who defied the Nation of Islam was Malcolm X. Ali's feet never moved.

What if they had?

This week we hit CTRL+Z on the step he refused, and follow the ripple to today: a quiet Sunday in Cleveland, a nickname that stays on a Harlem playground, a swimmer lighting the cauldron in Atlanta, and a roll call at the 2016 ESPYs that runs 1 name short. Nobody ever marches behind Muhammad Ali, because on the one afternoon it counted, Cassius Clay stepped forward.

SPOILER ALERT: This episode discusses the endings of The Sopranos, Breaking Bad, Lost, Parks and Recreation, Mad Men, The Leftovers, and Ozark.

On June 10th, 2007, David Chase ended The Sopranos with a family eating onion rings in a New Jersey ice cream parlor, a bell over the door, and 10 seconds of black. Viewers across the country hit their cable boxes. The Boston Globe's television critic sat through those seconds certain his set had died and taken the review with it.

Chase had spent years planning something else. Tony Soprano drives out of the Lincoln Tunnel at the top of all 86 hours of the show, and the last scene sent him back the other way, into Manhattan at night, to a meeting he wasn't walking out of. Then, driving down Ocean Park Boulevard in Los Angeles in 2005, Chase passed a little breakfast place, and a thought arrived: Tony should get it somewhere like that. The breakfast place won.

What if it hadn't?

This week we hit CTRL+Z on the last pages of the final script, and follow the ripple to today: a song that stays where it was in 1981, a corner booth in Bloomfield that stays furniture, a documentary that ends on an answer, and a decade of showrunners deciding what they owe an audience when the credits come. Nobody ever asks David Chase what happened to Tony Soprano, because 12 million people watched it happen.

On May 9th, 1933, guards climbed a scaffold in the lobby of the RCA Building and brought Diego Rivera down mid-brushstroke. His fresco for Rockefeller Center held a portrait of Lenin, and Rivera had refused Nelson Rockefeller's written request to paint it out. The wall got a canvas drape, and 9 months later, workmen chiseled 63 feet of plaster into powder near midnight.

Buried in Rivera's refusal letter sat a counteroffer almost nobody remembers. He would trade the mural's nightclub scene for Abraham Lincoln, standing with John Brown, Nat Turner, and Harriet Beecher Stowe. Lenin on one side, Lincoln on the other. Nelson, 24 years old, said no.

What if he'd said yes?

This week we hit CTRL+Z on May 8th, 1933, and follow the ripple to today: a finished fresco drawing Depression crowds past a communist in a capitalist lobby, a congressman waving photographs of the wall on the House floor, a velvet curtain going up in the McCarthy years and coming down for a funeral, and delegates at the 1964 Republican convention booing the man who kept it. Rockefeller Center destroyed the painting, hired another artist, and put Lincoln on that wall anyway. The mural Rivera lost became the most famous artwork America ever destroyed, and the version that survives hangs in an office lobby where tourists walk past it on the way to the elevator.

On January 25th, 1993, Sears killed the most famous catalog in American history, and Wall Street applauded. The Big Book was losing up to 175 million dollars a year, and Arthur Martinez, 5 months into the job, chose to eliminate it rather than shrink it. 113 stores closed. 50,000 jobs vanished. The last telephone order came in on May 27th.

Two weeks before the announcement, in White Plains, New York, a company called Prodigy passed 2 million subscribers and became the largest online service in America. It sold merchandise on a screen, years before the web. Sears owned half of it.

What if Martinez had connected them?

This week we hit CTRL+Z on January 25th, 1993, and follow the ripple to today: catalog buyers rebuilding an online store item by item, an electronic Wish Book selling Sega Genesis consoles at midnight, Jeff Bezos choosing books because a 100-year-old competitor already sells everything else, and a dot-com crash that kills every internet store except the ones sitting on real warehouses. Sears spent a century shipping goods to people who couldn't reach a store, built the screen that came next, and dismantled the machine 18 months before the future needed it.

In February of 1942, the ships carrying Australia's best soldiers were in the middle of the Indian Ocean, and Winston Churchill turned them around without asking. Singapore had surrendered 7 days earlier. Darwin had been bombed 3 days earlier. Churchill cabled Prime Minister John Curtin that the 7th Division was going to Burma, that some ships lacked the fuel to come home, and that the President of the United States agreed.

Curtin, 4 months into the job, said no. 4 times.

Every Australian prime minister before him had given London what it asked for. The convoy turned south, the men came home, and they held the Kokoda Track and won at Milne Bay, the first clear defeat of the Japanese army on land in the entire war.

What if he'd said yes?

This week we hit CTRL+Z on February 22nd, 1942, and follow the ripple to today: 5,000 Australians walking 900 miles out of a lost Burma, teenage militia holding a mountain track alone, a division stranded in Ceylon while its country waits, and a nation that signs the same American treaty in 1951 but signs it as a follower instead of a partner. Australia came within one midnight cable of staying a colony in its own head, and the refusal is where the modern country began.

In December of 1135, Henry the First of England died in Normandy, and the man best positioned to take his throne had already sworn twice not to. Henry had made every baron in his kingdom kneel and lay a hand on a chest of saints' bones, promising to crown his daughter Matilda after him. One chronicler says Stephen of Blois pushed to reach the relics first.

Stephen took a ship instead.

He was crowned at Westminster three weeks later, and England spent the next 19 winters tearing itself apart. A monk at Peterborough wrote that Christ and his saints slept. Out of that wreckage, Matilda's son built the writs, the traveling judges, and the 12 sworn neighbors that England, the United States, and most of the Commonwealth still run their courts on.

What if he'd kept his word?

This week we hit CTRL+Z on December 22nd, 1135, and follow the ripple to today:a woman crowned at Westminster 4 centuries before Mary the First, a warlord who dies old in his bed instead of excommunicated in the Fens, a child named William Marshal who never gets handed to a king as security for his father's promise, a northern border that stays where Henry the First left it, and an ordinary man with a stolen field who waits two generations for a court that will hear him. England came within one kept promise of its first queen, and the broken one is where the common law came from.

In 1980, the most respected executive in America needed a successor. Reginald Jones ran General Electric, a company of 400,000 employees and the last original member of the Dow, and he chose by calling each finalist into his office and asking the same question: you and I die in a plane crash, so who should run the company?

Jones picked Jack Welch.

Wall Street crowned him Manager of the Century, every boardroom in America copied him, and the doctrine he made respectable, the shareholder above everything else, still runs the economy you live in.

What if Jones had picked the engineer?

This week we hit Control Z on the vote of December 19, 1980, and follow the ripple to 2026: corporate raiders who die as convicts instead of prophets, two planes that land safely on mornings we remember for crashes, a machinist in Erie with a pension, and a middle class that never stopped getting raises. The old American deal came within one boardroom vote of surviving, and the man who killed it built his creed on its ashes.

4th of July Episode!

In 1776, one British general had George Washington cornered. Washington's army was trapped on a strip of high ground in Brooklyn, its back to a river with no boats, beaten and out of room. General William Howe's officers begged him to storm the position and end the revolution that afternoon. He told them to wait, and two nights later a storm and a fog let the entire rebel force slip across the water and escape.

That pause saved the United States before it existed. Howe had already lost more than a thousand men climbing a hill into American guns near Boston, and he refused to spend that many again for a victory he thought he could win slowly. His caution handed the rebellion seven more years, a French alliance, and eventually a country.

What if Howe had given the order to attack?

This week we hit Control Z on the assault Howe refused to launch, and follow the ripple all the way to 2026: a Washington who dies a forgotten farmer, an America that grows old under the Crown, a French king who keeps his head, and a twentieth century with no world wars to fight. The most powerful nation on earth came within one afternoon of never being born, and the man who saved it was trying to win the war for the other side.