The game sounds simple enough. Four people jump onstage and act out a two-minute version of a familiar children's story selected by the audience.

But in each successive round, one actor leaves the stage, until there is a single person left to play all of the roles and the story evolves into an unfamiliar, laugh-out-loud, overacted farce.

The game is called "Highlander," after the movie with the catch phrase, "There can be only one." On a recent Thursday, it capped an evening of low-cost, come-one-come-all, improvisational comedy practice at Roseville's Blacktop Comedy.

About 25 people, from senior citizens to teenagers, were on hand to enjoy the show and to take their own shot at demonstrating the quick wit needed to create the spontaneous routines.

"It's made me more out- going," said Skyler Buchman, 15, of Roseville.

In recent years, a number of "improv" comedy clubs like Blacktop have sprung up in the Sacramento region. Most offer classes as well as weekend shows, in which trained performers incorporate audience suggestions to create a raw, off-the-cuff comedy experience. The former television show "Whose Line Is It Anyway?" is often hailed as the gold standard of the improv technique.

"I definitely think (improv) is growing in popularity," said Brian Crall, owner of Sacramento Comedy Spot. He said it tests participants' ability to adapt and deal with stress.

"It's like a ropes (challenge) course without being in a tree. It's something that you can do that is a little bit out of your comfort zone," Crall said.

He said classes attract extroverts and introverts. Introverts tend to be more successful, he said.

The Thursday night class called "The Playground" at Blacktop Comedy is notable for the low barrier to participation and the breadth of performers/students.

At one end of the spectrum is Skyler, an eager, earnest but slightly awkward teen learning to trust his instincts and find his voice. His flipped-up flat-brim New York Knicks hat screams "knock me off."

At the other end are Ginny Southerland and Barbara Green. Both wear sensible clothing, are in their mid-60s and live in the mammoth Sun City Lincoln Hills retirement community. Southerland and Green have stage experience but wanted to get better at thinking on their feet. The two thrilled the audience with their version of "Jack and the Beanstalk."

"It helps you see the world onstage in a different way," Southerland said.

The evening starts with warm-up games, in which everyone participates, before moving to the stage, where a handful of participants take part in each game. Encouragement is liberal and the laughs come easy.

In recent weeks, the Playground has grown to the point where there are always plenty of volunteer performers. It wasn't always that way.

"The first couple months we probably had five people total (counting the two instructors)," said Betsaida Lebron, Blacktop's co-artistic director.

Owner Paul Burke, who has been doing improv for eight years, opened Blacktop in July. His comedy experience started with stand-up, but he said he craves the collective interaction provided by improv.

"I started to try to chase it wherever I could," said Burke.

That meant attending improv festivals and later studying at the "Mecca of improv," Second City in Chicago.

He said he is trying to bring that experience back to his theater, a converted warehouse in Roseville. In fact, he's practically giving it away. First-time visits to the Playground are free. Subsequent visits are $5.

Burke and Lebron are the teachers on Thursdays; on Saturday nights, they are the stars, working with two others in a four-person crew.

At a recent Saturday show, the four performers incorporated audience suggestions. In one bit, they stumbled onto some observational comedy that really hit home with the audience.

"No. 1 or No. 2? No. 1 or No. 2?," one actor repeated, as he acted out a familiar scene from an eye exam. The audience went crazy.

"It was hilarious," said Jen Underhill, of West Sacramento, after the Saturday show. She was there with two girlfriends, and all of them work in optometry. "I've never been so impressed with improv comedy."

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Call The Bee's Ed Fletcher, (916) 321-1269. Follow him on Twitter @SB_Ed_Fletcher.

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