Julianne Moore reveals in a new interview how she recruited actress Reese Witherspoon and a throng of other A-list Hollywood stars to join her campaign for gun control and opposition to the NRA.

Moore is aligned with Michael Bloomberg-funded Everytown for Gun Safety and used an interview with In Style to recount how her start with in the gun control lobby morphed into a star-studded movement against gun ownership.

The Oscar-winner explained that her desire to work with the gun control lobby began with the December 14, 2012, attack on Sandy Hook Elementary School. That attack centered around a 20-year-old gunman who stole firearms, killed his mother, then went to the school and killed 26 other individuals before killing himself.

Sandy Hook was gun-free, so the attacker was able to carry out his evil designs inside the school for a period of over nine minutes without armed resistance.

Moore said that shooting solidified her gun control convictions.

“I…felt I needed to do something to keep [my daughter] and all the other children in our country safe from gun violence, so I started speaking out against it and following other activists on Twitter.” She told In Style, adding that she “learned that [former N.Y.C.] Mayor [Michael] Bloomberg had formed this organization called Mayors Against Illegal Guns [which eventually joined Everytown for Gun Safety].”

The Hunger Games star committed to pull together a “Creative Council” for Bloomberg’s Everytown.

Everytown reports that celebrity Council members — in addition to Lawrence, Moore, and Witherspoon — includes Kirsten Dunst, Michael J. Fox, Bart Freundlich, Jim Gaffigan, Greta Gerwig, Bill Hader, Chelsea Handler, Melissa Joan Hart, Todd Haynes, Bryce D. Howard, Ron Howard, Helen Hunt, Spike Lee, Seth MacFarlane, Katie McGrath, Debra Messing, Megan Mullally, Olivia Munn, Conan O’Brien, Nick Offerman, Ed O’Neill, Yoko Ono, Gwyneth Paltrow, Sarah Jessica Parker, Amanda Peet, Kyra Sedgwick, Sarah Silverman, Russell Simmons, Tim Simons, Michael Stipe, and Liv Tyler.

Bringing together a Creative Council meant enlisting the help of friends. Moore said, “What I did was go to the most famous people in my contact list and ask them first. When they said yes, I would say, ‘Jennifer Lawrence and Reese Witherspoon and I are going to be on this thing. Will you do it?’” As fellow celebrities said “yes” to the gun control push, Moore said she would add their names to outreach for contacts to show that the gun control movement was growing.

Moore says the Creative Council now has “200 very active members.”