The Dark Knight trilogy composer Hans Zimmer recorded a special theme song for San Francisco’s Batkid, a representative for the artist confirmed.

Batkid took the world by storm late last week thanks to the Make-A-Wish Foundation, who teamed up with the city of San Francisco to turn the town into Gotham for a day. Several missions were set up around the city where 5-year-old, leukemia-striken Miles Scott took on villains like The Riddler and The Penguin. He was later given the Key to Gotham by the Mayor of San Francisco.

“Yes, Hans did write a score for Batkid,” Zimmer’s publicist Rae Murillo told Radio.com last week. “We’re not yet sure when or how the music will be incorporated, but I do know that there are different elements and surprises being rolled out as the day progresses, so we’re just waiting to see how the music is going to be used.”

The publicist said there were no plans to release it to the public, but a copy will be given to Miles.

A copy of Zimmer’s Batkid theme hasn’t surfaced online yet, and we don’t know at which point it was used on Friday.

Hans Zimmer scored this year’s Man of Steel for Zack Snyder, but as of September the artist was not sure if he’ll take on Batman VS Superman.