FIRST CAME the blessing, fervently delivered in mock nun-drag by the Sisters of Perpetual Indulgence. Then came as fine a fast-fingered, feedback-infused deconstruction of the national anthem as has been heard since the prime of Jimi Hendrix, at the hands of guitarist Liberty Ellman. Then the San Francisco Mime Troupe hit the stage.

And that's the good news. It wouldn't be a glorious Fourth in San Francisco without the Mime Troupe in Dolores Park to open its annual summer of free outdoor performances. The rockets wouldn't glare as red nor burst so brightly in air without the troupe's usual bracing dose of vibrant, radical musical political comedy.

Such was almost our fate last year, when drastic NEA cutbacks (worse yet are threatened once again) almost forced the troupe to cancel its summer show. Last-minute fund raising managed to salvage a severely truncated season, which was both a blessing and a pity. For "Soul Suckers From Outer Space," a fast-food sci-fi fantasy, turned out to be one of the funniest, cleverest and most provocatively endearing shows ever cooked up by Mime Troupe playwright Joan Holden and her colleagues.

This year's "Killing Time" isn't as inventively hilarious or cunningly plotted. Nor, on opening day, was it quite as tight a production. But Mime Troupe shows tend to get tighter and sharper as the season wears on, and this one will have plenty of time to pull itself together. This summer the company is back to a full schedule in San Francisco, Berkeley and Oakland parks through Labor Day.

Besides, even if "Time" suffers by comparison with "Soul Suckers," it's still a bona fide S.F. Mime Troupe outdoor show - smart, funny, refreshingly political and deftly performed. Which makes it one of the better ways to pass a summer afternoon.

Written by Holden, frequent collaborator Gregory R. Tate (the troupe's stage manager, who also plays a delightfully disaffected, sardonic, hulking jack-of-all-trades set changer) and Kate Chumley (Holden's daughter, and co-writer on "Soul Suckers" ), "Time" is a tale of youthful desperation in an era of capital concentration, corporate "right-sizing" and drastically lessening expectations for personal advancement or any crumbs of social justice.

Jacob (veteran local actor and troupe newcomer Michael Oosterom) is an office temp pushing 27 with no hope of ever securing a job with benefits or earning enough to begin paying back his college loans. When he finally lands a "permanent" position, the whole branch is downsized out of existence.

He returns home only to find his roommates packing up to move on (or back with their parents). Then his equally disillusioned and purposeless girlfriend, Cynthia (engaging troupe regular Keiko Shimosato), suddenly finds a cause she can believe in - saving the Headwaters Forest - and runs off with Forests First crusader David (a fervid Conrad Cimarra). Meanwhile, Margaret (the troupe's dynamic Velina Brown), a homeless Gulf War vet, moves in and tries to win Jacob over to her 10 Point Program for social change.

Margaret, racked with Gulf War Disease, is a victim of the same Galactic Electric that just laid off Jacob. GE downsized her husband, destroying her family, after having made the poison gas detectors that didn't work during the war.

None of which matters much to GE CEO Jack Belch (ever-reliable all-purpose troupe villain Ed Holmes). His biggest worry, in the midst of buying and closing companies and pushing the government around ( "This is global conquest, not Monopoly," he roars), is a heart he has to keep jump-starting by pounding on his chest. "Why can't I live forever?" he demands. "I can afford it!"

Everything comes to a head at the Bohemian Grove, where Jacob gets a job as a waiter, Belch is getting insider tips from Alan Greenspan (a comical Amos Glick), Margaret is stalking Belch, and Cynthia and David try to confront tree-destroyer Charles Hurwitz (guitarist Ellman). Jacob blows one chance after another of taking a stand for social justice, and ends up serving Belch's devious designs on immortality.

It isn't one of your more upbeat Mime Troupe endings, but that isn't what makes it less than satisfactory. Despite the sharp, energetic performances of Oosterom (who doubles in a brilliant caricature of a sincere, spineless Bill Clinton) and Brown, their characters haven't been well enough defined to give us much of an investment in their fates. Jacob's lack of ideals ("If I'm never gonna do something that counts, it might as well be something with benefits") removes any sense of suspense from what should be his moment of truth.

That said, "Time" offers plenty of dynamic entertainment and sharp social satire packed into less than an hour and a half. Longtime Mime Troupe composer Bruce Barthol and Ellman (with band members Eric Crystal and Derrek Phillips) contribute some strong numbers - Oosterom's grunge rock "Goin' Nowhere," Brown's insistent "Some Most All" and a brilliant trio of dysfunctional roommates, not to mention the hilariously New Age-y redwoods theme - although the "We Own It" CEO trio needs some punching up.

Director Michael Gene Sullivan and his designers come up with their usual comically creative solutions for the company's quick-change multiple roles (Shimosato designed the sharply caricatured costumes) and deft scene changes. The way Cimarra's distressed garage-door set becomes a corporate headquarters or a redwood grove is a stroke of genius.

And the actors handle their multiple roles with typical Mime Troupe comic skill. Shimosato is a delight doubling briefly as Belch's greedy, designing trophy wife, and Cimarra has a fine turn as Jacob's fed-up gay roommate. Holmes, with his customary devilish mastery, is almost lovably single-minded and manipulative as the unstoppably rapacious Belch.

"Time" may not rank as one of the Mime Troupe's more exciting efforts, but it does pack a lot of socially conscious entertainment into a pleasant summer afternoon.

The San Francisco Mime Troupe performs "Killing Time" Saturday and Sunday at 2 p.m. in Dolores Park, Wednesday at 12:30 p.m. at Yerba Buena Gardens, and in various Bay Area parks weekends through Sept. 1. All weekend shows are free and start at 2 p.m. For a schedule, call (415) 646-0639.