We've seen the newscasts. We've seen the trailer. But what we haven't seen is the real-life behind-the-scenes story of how 5-year-old Miles Scott became Batkid with the help of the Make A Wish Foundation and the people of San Francisco -- until now.
The Make A Wish Foundation released "Miles' Wish to be Batkid" on Wednesday, a nine-minute documentary on the small wish that took over a city.
"When I originally heard about this event, I thought it was going to be kind of small," said the man who played "Batman" at the event. "A few weeks later, I knew it was going to be big, but I had no idea."
"I thought we were going to have about 200 volunteers to help it make him feel like a real super hero and make it exciting," said a representative for Make-A-Wish in the video.
But after a volunteer posted the event to Facebook and the story was picked up by a blogger, it quickly went viral. When the day finally came, thousands of people filled the streets.
Watch the video above -- we dare you not to reach for a tissue.