Entertainment TV 'ER' Reunion! George Clooney, Noah Wyle and More to Come Together in Support of Waterkeeper Alliance The April 22 live reunion, which will stream exclusively on PEOPLE's social platforms, includes Gloria Reuben, George Clooney, Noah Wyle, Laura Innes, Anthony Edwards, Julianna Margulies and more By Natalie Stone Published on April 13, 2021 09:00 AM Share Tweet Pin Email Nearly 30 years after ER premiered, the beloved cast of the medical drama is reuniting! On April 22, multiple stars of the long-running series will come together for a live, virtual reunion on the daily series Stars in the House, PEOPLE can exclusively reveal. The reunion episode will feature cast members Gloria Reuben (Jeanie Boulet), George Clooney (Doug Ross), Noah Wyle (John Carter), Laura Innes (Kerry Weaver), Anthony Edwards (Mark Greene), Alex Kingston (Elizabeth Corday), Julianna Margulies (Carol Hathaway), Goran Visnjic (Luka Kovac), Paul McCrane (Robert Romano), Ming-Na Wen (Jing-Mei Chen), Laura Cerón (Chuny Marquez), Yvette Freeman (Haleh Adams), Conni Marie Brazelton (Connie Oligario) and CCH Pounder (Angela Hicks). Airing on Earth Day, the special episode will be held in benefit of the Waterkeeper Alliance — the fastest growing global nonprofit focused solely on clean water. Listen below to the episode of our daily podcast PEOPLE Every Day for our interview with Gloria Reuben and how she orchestrated the ER reunion. Reuben, who serves as the president of the organization, thought it would be fun to bring the cast back together in support of the nonprofit. Noah Wyle Looks Back on ER 25 Years Later, Reveals Why He Doesn't Think a Reboot Will Happen ER cast. Chris Haston/NBCU "I am absolutely thrilled to be reuniting with my ER family for a cause that is so close to my heart, and so grateful to Seth and James for allowing us to use their incredible platform to do so," Reuben, 56, said in a statement. "I've been involved with Waterkeeper Alliance for 15 years, representing over 350 community-based Waterkeepers around the globe, and the work that they do is beyond comparison," she continued. "We must continue to fight for clean water not just on Earth Day, but all year round!" Cast of ER. Sven Arnstein/NBCU Hosted by Seth Rudetsky and James Wesley, the episode will see the cast reminisce about their time at Chicago's County General Hospital and answer live questions from fans. Created by Michael Crichton, the series ran for 15 seasons from 1994 to 2009. In 2019, Grey's Anatomy made history as the longest running medical drama on American television (with 332 episodes!) — surpassing ER. The Cast of ER: Where Are They Now? Cast of ER. Getty Images "ER was one of the shows that made me want to write television," Grey's showrunner Krista Vernoff exclusively told PEOPLE during a set junket that year. "It changed TV and it forged a path for Grey's Anatomy to come. We walked in ER's footsteps and we're forever grateful. It's amazing to me that we're breaking that record. I'm just blown away!" The ER stars join a growing list of casts that have been brought together for a good cause on Stars in the House. Other casts that have reunited include Night at the Museum, Knots Landing, Melrose Place, Frasier, Glee, 30 Rock, Desperate Housewives, Family Ties, Scandal and more. The upcoming reunion will stream exclusively on PEOPLE's social platforms — Facebook, Twitter and YouTube — as well as on PeopleTV's Facebook and Twitter, on Thursday, April 22 at 8 p.m. ET.