It's not uncommon for theater companies to try out plays in readings — generally single-night affairs with invited audiences and a cast of actors who sit on the stage without props, costumes, lighting or set design, accompanied only by scripts.

The reading of a new play called 8 at the Wilma Theater on Monday evening will be a little different. It will still be theater without the trimmings, but open to the public at $20 a ticket. The play has become a theatrical event in cities across the nation in the last few months, with 140 future bookings on professional, community, and college stages that stretch into 2013 and as far away as Canada, Australia, New Zealand, and Zimbabwe. It was written to be produced in a reading, and for a specific cause.

The 90-minute play, about marriage equality, is called 8 after California's Proposition 8, which declares that marriage in that state can legally be only between a man and a woman. Proposition 8 won by a narrow margin on a 2008 ballot, only months after California's Supreme Court decided that banning same-sex marriage was against the state's constitution.

At that time, a grassroots organization of theater artists called Broadway Impact formed in support of marriage equality, and its members are the organizers of readings of 8, which has so far played in 26 cities and raised more than $3 million. The money goes to the American Foundation for Equal Rights, the sole sponsor of a federal court challenge to Proposition 8 on constitutional grounds. As of now, the U.S. Court of Appeals for the Ninth Circuit has ruled that Proposition 8 is unconstitutional, and supporters of Proposition 8 are appealing that decision. Meanwhile, the play by Oscar-winning screenwriter Dustin Lance Black (Milk, J. Edgar) continues to raise funds for the court battle. The story traces the reaction to Proposition 8 by using two real-life couples as its main characters; Black's script contains actual testimony for and against the ban, and examines the way the challenge affects the plaintiffs.

The Wilma Theater's reading mixes Broadway actors with the city's theater community in a 22-member cast. "It's been amazing, the support we've had," says Jenny Kanelos, a former movie production coordinator and theater manager and one of the three founders of Broadway Impact. "Actors are ready to jump in a car and come down to Philadelphia to join the cast." At the Wilma, they will include the two other Broadway Impact cofounders, Gavin Creel (Hair) and Rory O'Malley (The Book of Mormon).

Kanelos says that a You Tube version of the entire reading of 8 in Los Angeles several weeks ago — for which Broadway Impact partnered with both Google and You Tube to record — has increased interest among possible presenters and theatergoers who want to see it live. "We got about 150 inquiries after that went up," she says.

The Wilma became involved last winter, when New York-based actor Benjamin Pelteson, a member of Broadway Impact who will be in the cast of the Wilma's forthcoming Angels in America: Part One, suggested that the theater company stage a reading of 8. "It was a no-brainer," says Walter Bilderback, the Wilma's literary manager and dramaturg, who will direct the reading.

The timing was perfect. Part One of Tony Kushner's celebrated two-part play opens later this month at the Wilma; it's his eloquent riff on AIDS, gay issues, and social concerns in America in the '80s. "We've very concerned about the present-day resonance of Angels in America," says Bilderback, "and that it's not just a museum piece. AIDS is still a problem, but not the killer it was in the '80s."

Bilderback points out that one of the play's main gay characters declares in Part Two, which the Wilma will stage in the fall, "We will be citizens!" Says Bilderback: "It seems like the issue of marriage equality is very much part of the process of allowing everyone to be citizens."

The cast at the first reading of 8, last fall on a Broadway stage, included Morgan Freeman, John Lithgow, Christine Lahti, Ellen Barkin, Cheyenne Jackson, and Rob Reiner. In Los Angeles (and on the recorded version on YouTube) the cast included George Clooney, Martin Sheen, Jamie Lee Curtis, Brad Pitt, and Matthew Morrison.

At the Wilma, the cast will include Randy Harrison (TV's Queer as Folk), Philadelphia native Phillip Spaeth (Smash), Philadelphian Forrest McClendon (The Scottsboro Boys on Broadway and at Philadelphia Theatre Company), Hunter Bell (the musical called [title of show]), and Charles Socarides (Off-Broadway's Sons of the Prophet).

Among the Philadelphia actors in the cast is John Jarboe. "I think it's rare when an especially larger theater institution can take on a story that has immediate political meaning," says Jarboe, 25, who appears on various area stages and is a gay man who's created his own work about equal rights. "I'm really glad to be doing something like this, and on a larger scale."

Several Philadelphia actors visible in the region's theaters are able to be in 8 because the show's reading is Monday, when most stages are dark. These include Grace Gonglewski, who is currently in 1812 Productions' Boston Marriage; Steve Pacek, appearing in Arden Theatre Company's family show Robin Hood, and Mary Martello, now in Act II Playhouse's My Fair Lady.

"It's a reading — but you work," says Martello, who addresses the point that a reading may be no-frills theater, but it's acting, nonetheless; the Wilma is offering a $75 honorarium to everyone in the cast, which will spend all day Monday rehearsing before the 7:30 p.m. performance. "The Wilma," says Martello, "has been good to me and if they call and I can be available, I'm going to be available for them."

Contact Howard Shapiro at 215-854-5727 or, or #philastage on Twitter. Read his recent work at Hear his reviews at the Classical Network,

Theater 8 7:30 p.m. Monday at Wilma Theater, 265 S. Broad St. $20. 215-546-7842 or