Death is the end of all true stories.

Let's tell a lie instead.

Schrodinger may have been thinking of the many-worlds interpretation as early as 1952, but the first person to truly explicate it was the physicist Hugh Everett, in 1957. Others ran with the concept, and it's quite popular nowadays among scientists and laypersons alike.

At its heart, the many-worlds or multiverse interpretation is an effort to solve a problem in quantum mechanics. All the smallest things in nature appear to have uncertainty built into them. On that very miniscule level, we cannot tell everything that is happening. But out here in the real world, things do, visibly, happen. And these things we can see are entirely controlled by these unknowable tiny forces.

It's somewhat like a religion, in that way, but there are very complicated maths involved so it must be true. Just roll with it.

The many-worlds interpretation takes care of that uncertainty by saying that everything that doesn't happen here still happens someplace. Every possible wibble of every subatomic particle that can't be measured… wobbled the other way, somewhere. The left-wibble vs. right-wobble universes have split off, an infinity of infinities spiraling off from every single one of these endless infinitesimal motions.

Many of these universes, logic would tell us, are functionally identical to our own. On the macroscopic scale, a single electron in a single hydrogen atom's opting for "up" over "down" doesn't usually make much difference to the price of tea.

Some universes, particularly the ones that split off earlier, must be wildly different. More unlikely. Ones where the asteroid didn't strike and the dinosaurs still walk the earth. Or where La Resistance successfully defeated the Nazis in World War II and set the stage for a two-hundred year dominion of French communists over the world's government. Or where Sherlock Holmes and Doctor Watson are beloved fictional characters invented by Sir Arthur Conan Doyle in 1887, appearing in fifty-six short stories and four novels by the same author over the next forty years.

And sometimes, somewhere, the differences are subtle but incredibly significant. A woman sees the threat and starts to move a fraction of a second earlier. Another woman pulls the trigger a fraction of a second later. The bullet still flies on its inexorable trajectory. It still hits its unintended target… just one inch to the right.

In both universes, Mary Watson, forty-one, married, mother of one, ex-covert operative, current nurse, bottle blonde, strikes the floor. In both, she is carried away shortly thereafter.

In one, she's carried away still breathing. Just barely. But breathing.

This is that universe.

The stage is set, the curtain rises. We are ready to begin.