Replace Jimmy Stewart's wide-eyed optimism in "Mr. Smith Goes to Washington" with some good ol' Bay Area satirical cynicism and you've got this year's San Francisco Mime Troupe offering, "Mister Smith Goes to Obscuristan."

After its successful, traditional Fourth of July opening in Dolores Park and a quick jaunt to the East Bay, the troupe comes back to The City this weekend for more free performances in Glen Park (Saturday) and Yerba Buena Gardens (Sunday).

This year's installment of mime troupe mayhem was written by the group with assistance from Josh Kornbluth, known for his theatrical comic monologues, as well as "Haiku Tunnel," a film set in The City and released last year. Kornbluth has a nice, light touch. His writing contribution reflects and respects the company's dedication to political skewering and goofy impersonations.

As usual, the laughs in the dialogue are punctuated by funny songs, with lyrics by Bruce Barthol and music by musical-director keyboardist Jason Sherbundy.

The story starts out in Obscuristan, a poor, seemingly Middle Eastern country where American TV reporter Marcy Chang (Keiko Shimosato) is about to cover the first-ever democratic election. But the censored news network newswoman is quickly called off the story.

Cut to the White House, where pretzel-chomping George Dubbya Bush (Amos Glick in an overdone, but still laugh-inducing bit), Dick Cheney (Ed Holmes) and Condoleezza Rice (Velina Brown) scheme to ensure that Obscuristan voters are limited to one candidate, the U.S.-supported Automaht Regurgitov (Victor Tolman), who'll protect American business interests in the country's untapped resources.

Their plan is to send a true-blue American hero, New York firefighter Jefferson Smith (Michael Gene Sullivan, who directed the show), to "monitor" the proceedings.

But complications arise when Ralif Nadir, a real candidate preaching democratic principles, comes on the scene and catches Smith's attention.

The troupe displays its trademark dexterity, and many of the jokes hit. But compensating for the ones that don't are all the other amusing elements of a standard mime troupe event: For example, the cast members playing multiple roles, the speedy costume changes, and the low-tech but completely functional set design that easily moves from Obscuristan to Washington, D.C.

While all of the actors are versatile, two made a big impression during the production's third performance of the season. (By the way, this summer marks the group's 41st year.) Brown, belting an R&B number that could rival Tina Turner, stood out as an ambassador who convinces Smith to do his American duty.

Meanwhile, Holmes stole the show with a hilarious cameo as the president's take-charge mom -- string of pearls and all.