It is the year 2008, and the Terminator has come back through time with a vital mission: to protect the only three musical-theater actors on Earth who are capable of starring in the musicals of Stephen Sondheim. In this sci-fi world, where Broadway is allowed to put on nothing but revivals, those performers -- Michael Cerveris, Alexander Gemignani, and Raul Esparza -- must absolutely not be allowed to disappear.

This spoof of an idea, said South Pacific cast member George Merrick (Lt. Buzz Adams) the other day, is the scenario he dreamed up for the show's entry in the annual "Gypsy of the Year" competition. "Of course, I think Sondheim is the greatest," Merrick said. "But with his Road Show [currently off-Broadway at the Public], as with other recent Sondheims in New York, I asked myself a question: "What are those three actors doing -- and they are all very talented -- that is so amazingly above and beyond? Why does it seem that no other actors are even seen for Sondheim shows in New York anymore? I wanted to do a loving send-up, with a roll of the eyes."

That send-up was performed yesterday and again this afternoon at the New Amsterdam on 42nd Street to benefit the theater charity Broadway Cares/Equity Fights AIDS. It's part of a competition that caps off a month of fundraising after performances of shows in New York and around the country. The event features skits -- some satirical like South Pacific's, others movingly serious -- in which "gypsies," or ensemble members, make fun of the theater scene. The numbers are full of in jokes that might mean nothing to someone who's never spent time backstage on Broadway, but that convulse the Gypsy of the Year audience, filled as it is with show folk.

Merrick's Terminator sketch lasts about three and a half minutes. It consists mostly of dialogue, with a voice-over to set the scene and a send-off tag in the spirit of a movie trailer: "Coming next summer at a theater to be announced." Cast member Charlie Brady plays the Terminator, electrical-crew member Kristina Melike Clark the female Terminator. Ensemble member Nick Mayo directed the sketch, and portrays Gemignani. Ensemble member Greg Roderick is Cerveris and Merrick does Esparza. Laurissa Romain (Ngana), Luka Kain (Jerome) and their real-life mothers, Laurie Sheppard and Lisa Calli, are also onstage.

The costumes were especially inspired. "We wanted the character to be identifiable," Merrick said. "Which meant a biker jacket for the Terminator and leather body suit for the female Terminator. Also Cerveris is there decked as Sweeney Todd, Esparza in the black suit he wore in Company, and Gemignani in overcoat, hat, and scarf. We hope people are amused."

Postscript: Not only was the South Pacific skit well-received, but the show was the third highest Gypsy of the Year fundraiser, with a total of $140,552 garnered for Broadway Cares/Equity Fights AIDS. That total was surpassed only by Equus and Wicked. This year, the entire Gypsy of the Year cause raised $3,061,148.

BRENDAN LEMON is the American theater critic for the Financial Times and the editor of lemonwade.com