A number of celebrities will descend upon DC along with a reported 500,000 marchers for the March For Our Lives.

Jimmy Fallon announced on his show on March 20 that he will march in Washington, D.C. in support and encouraged his viewers to also support the cause.

Justin Timberlake appeared in a video with Mayor Bowser on March 19, announcing his support for the March for Our Lives.

Lin-Manuel Miranda, the mind behind Broadway hits Hamilton and In the Heights, recently teamed up with the star of Broadway musical Dear Evan Hansen, Ben Platt, in a musical mashup. The two actors combined Dear Evan Hansen's "You Will Be Found" and Hamilton's "The Story of Tonight," titled Found Tonight. The duo announced they will not only be participating in the march, but they will be performing their collaboration there as well.

David Hogg, a Parkland shooting survivor and activist, announced Thursday that singers Ariana Grande, Jennifer Hudson, Miley Cyrus and Demi Lovato will stand with the marchers on Saturday by performing.

More performers and speakers will be announced in coming days.

"We're gonna have four major independent women that are standing with us and walking beside us, and those are Ariana Grande, Jennifer Hudson, Miley Cyrus and Demi Lovato. They're gonna be standing there with us and marching with us and they're some of the few people that are really coming out and stepping up with us," Hogg said.