Yes, Dr. Doug Ross will be there.

The cast of "ER" will reunite on "Stars In The House" for a special Earth Day episode for Waterkeeper Alliance, producers Seth Rudetsky and James Wesley have announced. Waterkeeper is the fastest growing global nonprofit focused solely on clean water.

Gloria Reuben, who played physician assistant Jeanie Boulet on the show and serves as the President of Waterkeeper Alliance, organized the cast to return one more time.

Reuben will be joined by 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) for an evening of reminiscing about their time at Chicago's County General Hospital.

"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 said in an announcement for the event.

The reunion will stream on April 22 at 8 p.m. EST on People magazine's official Facebook, Twitter, and YouTube, as well as on PeopleTV's Facebook and Twitter, and on the Stars In The House YouTube channel, and StarsInTheHouse.com.

Viewers will be able to ask questions live and donate to Waterkeeper Alliance.