Lin-Manuel Miranda is making music for a cause close to his heart…

The 37-year-old composer, lyricist, playwright, and actor, best known for creating and starring in the Tony Award-winning Broadway musicals Hamilton and In the Heights, has organized what could be an all-star charity single to raise money for disaster relief in Puerto Rico in the aftermath of Hurricane Maria.

Miranda hasn’t revealed the song’s title yet, but it will be available on October 6, according to CNN.

Miranda, whose parents came to the United States from Puerto Rico, said he “called every Puerto Rican I know” to contribute to the song. Two of the people participating are singer Ruben Blades and Hamilton castmate Anthony Ramos, who each belt out “Puerto Rico” in brief previews Miranda posted to Twitter.

“I had the idea at 3 in the morning. … The initial demo was me singing in a bathroom,” Miranda told CNN. “To every artist, I’ve said, ‘Can you help out on this song?’ And they said yes. Without even hearing the song, everyone’s joined in.”

“Puerto Ricans, that’s 3.5 million American citizens, just like Texas, just like Florida. I know there’s a tendency for fatigue because we’ve just been through two hurricanes. And we can’t be fatigued when it comes to our fellow Americans,” Miranda told CNN of the crisis in Puerto Rico, where many people are still without power and running short on basic supplies.

Miranda said his family in Puerto Rico is “all right,” but “there were a few terrifying days where nobody heard from anyone.”