Brad Pitt and George Clooney will lead an all-star cast in the Los Angeles reading of a play based on the trial over the constitutionality of California's gay marriage ban, Proposition 8.

8, which was written by Milk scribe Dustin Lance Black, will be streamed live Saturday starting at 7:30PM PST on the YouTube channel of the American Foundation for Equal Rights (AFER), the group formed specifically to support the legal challenge.

Rob Reiner, an AFER founding board member, invited America to watch the play in a video posted Thursday. (The video is embedded in the right panel of this page. Visit our video library for more videos.)

The 2010 trial, which was held in San Francisco, resulted in federal Judge Vaughn Walker, now retired, declaring the 2008 voter-approved amendment unconstitutional. A 3-judge appeals panel last month upheld Walker's ruling. Proponents of the ban have asked the court for a wider review.

The Los Angeles reading of the play also stars Jamie Lee Curtis, Matt Bomer, Martin Sheen, Jane Lynch and George Takei, to name a few.

The Broadway premiere of 8 raised over $1 million for the fight to win marriage equality.

(Related: Nearly 60 percent of California voters support gay marriage.)