Miles, a cancer patient whose leukemia is now in remission, spent an entire day pretending to be Batman while over 25,000 people played along.
San Francisco turned into Miles' very own Gotham City.
And now there's a trailer for a documentary, Batkid Begins, about "what happens when an event goes unintentionally viral."
The events surrounding Batkid are a reminder of all the good that can happen when human beings come together.
"In helping him to live this dream, we were saving ourselves," Chris Taylor, Deputy Editor of Mashable, says in the trailer.
We believe in Miles. We believe in Batkid. We believe in Gotham City.
Watch the full trailer here:
