Fully-nude bareback riding and "genital-to-genital touching" are among the acts that background performers on the show may be tasked with at a Wednesday shoot.

Background actors — extras — for HBO’s Westworld were being required Tuesday to sign a nudity and sex consent form that reads like the Kama Sutra and that has SAG-AFTRA officials worried that performers won’t realize that if they get cold feet on set they have the right to withdraw.

Indeed, cold feet may be the least of a performer’s worries.

The explicit consent form itself wouldn’t pass standards reviews at a broadcast network as it recites that the performer "may be required to perform genital-to-genital touching, simulate oral sex with hand-to-genital touching, contort to form a table-like shape while being fully nude, pose on all fours while others who are fully nude ride on your back, [and] ride on someone's back while you are both fully nude."

Less strenuously, others might simply "have [their] genitals painted."

The consent form is on Central Casting letterhead. On Wednesday, HBO issued a statement disavowing the notice and some of the details: “The document that the background actors were given was created by an outside extras casting vendor. It was not requested, written or approved by HBO, Warner Bros. Television, or the producers, and contains situations that we do not require of any actor. We are rectifying immediately the discrepancies in this vendor’s document with our actual on-set practices, which provide a professional and comfortable working environment for all performers.”

Later on Wednesday, SAG-AFTRA fired back: "SAG-AFTRA sent the consent form to HBO yesterday afternoon and requested that the document be changed to more accurately reflect the contractual provisions. HBO had every opportunity to rectify this situation and it was only after their direct refusal to remedy this that we posted the notice on our website. The Union is very pleased to hear that HBO is doing the right thing now, but it is disappointing that we had to take such public measures to ensure compliance with our contracts and protect our background actors."

Like all lists drafted by a lawyer, the consent form list includes catch-all language at the end, indicating that the actor may also be pressed into service to perform "other assorted acts the project may require." The imagination wanders at that phrase, but an omission from the form suggests that whips and chains may be off the table: the union contract requires advance notice of "rough or dangerous" work, and no such warning appears on the form.

Still, if any of those "assorted acts" verge on stunt work — as seems within the realm of possibility — the union contract may entitle the actor to be upgraded to principal performer, which brings with it residuals and a boost in pay.

The union agreement also requires additional payment when a background performer is asked to bring specified wardrobe. However, no additional payment is required when the performer is told to bring no clothing whatsoever.

The 2016 Westworld, described as "a dark odyssey about the dawn of artificial consciousness and the future of sin," is inspired by the eponymous 1973 Michael Crichton film that starred Yul Brynner and is produced by J.J. Abrams’ Bad Robot Productions, Jerry Weintraub Productions and Jonathan Nolan and Lisa Joy’s Kilter Films in association with Warner Bros. Television. The star-studded cast includes Anthony Hopkins,Ed Harris,Evan Rachel Wood,James Marsden,Thandie Newton and Jeffrey Wright.

A SAG-AFTRA member alert advises background performers that they have the right to withdraw consent at any time except as to scenes already shot, and that the set must be closed and still photography prohibited without the actor’s consent. The shoot takes place Wednesday, and a SAG-AFTRA representative will be at or near the set. The guild only tends to send member alerts when it is concerned.

Those protections only apply to union extras who are the first 19 on a television show. They’re usually referred to as "covered background performers," though in this case it seems that they’ll be covered by almost nothing except the union agreement.

The consent form includes a Central Casting logo that indicates the company was established in 1925, about a decade before SAG itself. The form is no doubt of more recent vintage and would not have been necessary in a pre-union era when movie companies were free to demand table-like nude contortions with abandon.

But today, the union agreement requires that producers obtain the performer’s advance written consent to nudity and sex acts, so the attorney who dutifully drafted the unusual form was apparently simply following the rules. The result, more risque than the usual boilerplate waivers, was probably not just another day at the office for its creator.

9/30/15 3:50 pm updated with HBO comment.

9/30/15 5:50 pm updated with SAG-AFTRA response to HBO comment.

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Email: jh@jhandel.com