Michael K. Williams and Ivory Aquino join the cast of ABC’s event limited series “When We Rise.”

Williams portrays African American community organizer Ken Jones, and Aquino plays the role of transgender activist Cecilia Chung.

“When We Rise” chronicles the real-life personal and political struggles, setbacks and triumphs of a diverse family of LGBT men and women who helped pioneer one of the last legs of the U.S. Civil Rights Movement from its turbulent infancy in the 20th century to the once unfathomable successes of today.

Joining the cast in part one (of this seven-part series) as special guest stars are Whoopi Goldberg as Pat Norman, the first openly gay employee of the San Francisco Health Department; Rosie O’Donnell as Del Martin, co-founder of the first lesbian organization in the country; Denis O’Hare as Jim Foster, openly gay Democratic party organizer; and David Hyde Pierce as Dr. Jones, Cleve’s father.

The event limited series is executive-produced by Dustin Lance Black (“Milk,” “Big Love,” “J. Edgar”), Laurence Mark (“Julie & Julia,””Dreamgirls,””I, Robot,” “Jerry Maguire”), Bruce Cohen (“American Beauty,” “Milk”) and Gus Van Sant for ABC. Van Sant will direct the two-hour premiere of the seven-episode event limited series.

“When We Rise” is written and created by Academy Award-winning screenwriter Dustin Lance Black and produced by ABC Studios.