Rachel Griffiths, Mary Louise-Parker and Guy Pearce are set for lead roles in When We Rise, ABC’s seven-episode event limited series about the gay rights movement, written and executive produced by Dustin Lance Black.

When We Rise chronicles the personal and political struggles, setbacks and triumphs of a diverse family of men and women who helped pioneer one of the last legs of the U.S. civil rights struggle.

Pearce (Memento, L.A. Confidential) will play LGBT activist Cleve Jones, Parker (Weeds, Angels in America) is women’s rights leader Roma Guy, and Griffiths (Brothers and Sisters, Six Feet Under) plays her wife, social justice activist Diane. The roles of African-American community organizer Ken Jones and transgender activist Cecelia Chung are still to be cast, among others.

Pearce, Griffiths and Parker join Austin McKenzie as younger Cleve Jones, Emily Skeggs as younger Roma Guy, newcomer Jonathan Majors as younger Ken Jones, and Fiona Dourif as younger Diane.

Gus Van Sant will direct the two-hour premiere of the miniseries and executive produce with Black, Bruce Cohen and Laurence Mark.