Uh-oh. Sarah Michelle Gellar is in tears, and she's having a hard time composing herself in front of her red-faced costar. ''You are just magic,'' she gushes after one take. ''I am just so in awe of everything you do.'' Her scene partner takes the awkward moment in stride he's used to it, after all. He's Elmo, and he's been sending stars into giggly, giddy freak-outs all week long.
Once a year, the storied children's-television institution known as Sesame Street packs up its puppets for the West Coast to film scenes with big names who might not be able to make it to the Queens set. During one week in April, the likes of Charlize Theron, Halle Berry, Jon Hamm, Melissa McCarthy, and Don Cheadle showed up at a Hollywood soundstage, where they explained words like innovation, vote, and remember to Elmo and Zoe. (Most of the segments will run throughout the 43rd season, which premieres Sept. 24 on PBS.) ''We call it a celebrity car wash,'' says head writer and puppeteer Joey Mazzarino. ''Every 45 minutes there's a new star walking through the door.''
Unlike so many projects in this town, Sesame Street has little trouble getting celebrities to sign on. More than 400 A-listers from Oprah to Johnny Cash have spent time on the Street dating back to season 1, when James Earl Jones flawlessly enunciated the alphabet. ''We have a long list of people dying to be on,'' says exec producer Carol-Lynn Parente. ''It comes down to who is available and what type of skit we need to film.'' (Two famous faces Sesame has yet to land: Bruce Springsteen and Barbra Streisand, who've turned down multiple offers to appear on the show.) Whether a tot recognizes Jon Hamm is irrelevant; Parente says research shows that children who watch with a parent learn better and Mom and Dad are more likely to watch if they see a celebrity.
While stars don't pick their puppet, they do get script approval. ''I try to write the script for the person, depending on if it's a comedy star or sports figure,'' says Mazzarino. ''But I love when people like Melissa McCarthy or Steve Carell come in and improv.'' Scoring a Street gig is like landing a front-row seat at the Oscars. ''I begged them to let me do it,'' says Gellar, whose 2-year-old daughter, Charlotte, is treated to an impromptu rendition of ''Charlotte's World'' courtesy of Elmo. ''I said I'd fire my representation if I didn't get to do this.'' After shooting a bit about the word reinforce, Joseph Gordon-Levitt is clearly reluctant to leave. Taking off his mic, he says, ''Do you want me to do another take? I will. I'll stay all day if you want!''