High drama and high humor are the treasures to be found in Shanghai San Francisco's 21/2-hour "scavenger hunt" through parts of North Beach, Chinatown and downtown.

By day's end, the eight members of our tour – mostly strangers from Sacramento, Sausalito, Tiburon and Berkeley – agreed the adventure was well worth the walk.

The interactive, street- theater plot is based on mid-19th century San Francisco, when the waterfront area was known as the Barbary Coast. It teemed with gangs, saloons and bawdy houses, and city government was notoriously corrupt.

One of the most vicious gangs was the Bowery Hounds, drawn from New York by the Gold Rush. The Hounds would kidnap (or shanghai) men and market them as laborers aboard ships bound for the Far East.

Fed up and ready to impose a little rough justice on the Barbary Coast, a group of San Francisco businessmen and lawmen formed the Committees of Vigilance in 1851 and 1856. Lynchings were part of their repertoire.

"The days of the Barbary Coast were the palette from which we created our story," said producer Joseph Tomasini, who founded Shanghai San Francisco three years ago. "We were thinking, 'What if members of the Committee of Vigilance and the Bowery Hounds still existed?' "

During the walk, our group encountered a dozen actors – vigilantes and Hounds – whose provocative role-playing moved the story forward. Participating, too, were "civilians" enlisted to play along with the company's Saturday excursions: bartenders, restaurant hosts, hotel employees, cab drivers.

The game was afoot when we gathered at Coit Tower and were contacted by an "agent" whose over-the-top intensity and one-liners had us laughing. He passed on vital information, foreshadowed events to come and directed us to our next contact.

We learned that the Hounds were back in San Francisco, had kidnapped one of the last four Committee of Vigilance members and wanted to ransom her for bullion that the committee had guarded since the Gold Rush. Our group had been enlisted to act as agents for the committee, rendezvous with key characters and follow a trail of clues that would allow us to rescue the victim. Maybe.

As we walked from place to place – often with a menacing character tailing us – we put our heads together to tackle puzzles (who was that North Beach celebrity?), figure out upcoming scenarios (via song lyrics, in one case) and solve clues (a series of photographs, a taped cry for help, a dramatic video, whispered words).

As our journey played out and clues were unraveled, we learned where to go for our next encounters. Some of our confrontations with the actors drew "only in San Francisco" stares from startled passers-by, which added spice.

At one point, we paused in a restaurant for refreshments and to discuss another clue.

"This works only if you play the game and get involved," said Barbara Malone, a group member from Sausalito. "It's fun, but some of that comes from being out in the city and seeing all that's going on around you."

Add a dash of paranoia to the vibe. At the start of the game, we were cautioned, "Trust no one." Would that come back to haunt us? Walking through Chinatown later – not knowing if we were being followed or what our next stop would bring – group member Jennifer Shepherd of Tiburon said, "My friends and I are having a great time, but I'm getting a little on edge. Somebody said 'hi' to me back there, and I didn't know whether to say 'hi' back."

Abruptly, the plot took an unexpected turn when surprising new information was learned. Then complications arose, and we had to take a chance and risk our safety.

We nervously accompanied a shady character down an empty alley and through a door that led to a totally unexpected venue.

What was in the locked box? Was there a fistfight? Was someone deceived? Double-crossed? Were we able to rescue the shanghaied victim in time and save the day?

Sorry – I really can't say.

SHANGHAIED IN S.F.

Shanghai San Francisco offers a "fun and mystery" walking tour in which participants become part of a "life-and-death mission" on a treasure hunt through parts of the city.

Cost is $40 per person.

Tours are at 12:30, 1, 1:30, 2 and 2:30 p.m., Saturdays only.

Corporate team-building groups can be accommodated on weekdays. For more information: www.shanghaisanfrancisco.com.

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