On a computer, Control Z is the undo button. When you press it, whatever you just typed gets reversed and allows you to make a different decision.

What if you could press control Z on some of the biggest decisions in history?

In October of 2016, Bob Iger was 48 hours from buying Twitter for $15 billion. Both boards had approved. The lawyers were drafting. Goldman Sachs was working the weekend. Then Iger went through the user data one more time, read his own notifications, and couldn't sleep. Sunday morning he typed an email to his board with the subject line "cold feet," called Jack Dorsey, and killed the deal. Twenty-eight days later, Donald Trump won the presidency.

Fourteen months after that, Disney bought 21st Century Fox instead, and Disney+ followed.

This week we hit Control Z on the Sunday morning phone call, and follow what happens when the man who runs Disney decides to own the platform that hosts the president.

In November of 1095, a sixty-year-old French pope stood in a field outside the cathedral of Clermont and gave the most consequential speech of the Middle Ages. Eight months earlier, ambassadors from the Byzantine emperor had asked him for a few thousand professional knights to help fight the Seljuk Turks. Standard contract work. Urban II sat with the request through the summer, then walked outside on November 27th and offered something nobody had ever heard before. Full remission of sins for everyone who took the cross. The crowd shouted back, "Deus vult." God wills it.

They asked for soldiers. He gave them a holy war.

This week we hit Control Z on the speech that launched the Crusades, and follow what happens when one man writes the smaller answer.