Lifegame, a unique performance piece in which actors tell the life story of a pre-selected guest, makes its Manhattan debut Sept. 12, after causing a sensation in England and southern California.

Created by improvisational theatre artist Keith Johnstone and realized by members of Britain's Improbable Theatre, Lifegame is billed as spontaneous and risky storytelling, offering a new character and a fresh life story eight times a week.

New York performances will be at the Jane Street Theatre, with direction and design by Improbable's Phelim McDermott, Lee Simpson and Julian Crouch (who also appear in the piece). Crouch and McDermott directed Shockheaded Peter, seen in the U.S. in 1999-2000.

Unlike traditional improv, which might have audience members shouting ideas to a team of actors, Lifegame seeks to celebrate the humanity and drama possible in everyday, ordinary lives.

The show is rooted in a Johnstone game called "How It Was." Like that theatre exercise, Lifegame attempts to find out as much as possible about "how it was" for a person as he or she was growing up, and in turning points of their adult lives. "There's one game played where you try to recreate a family meal or a family outing," co-director and co-designer Phelim McDermott told Playbill On-Line by phone from England. "Sometimes, when you hit a vein, they will say it's uncanny."

At every show, a different pre-selected and completely willing guest is asked questions about his or her life. Based on the stories they tell, the seven-member British ensemble acts out scenes from the person's past. The show has an open-ended run and, eventually, American actors will take on the storytelling tasks. Official opening is Sept. 28.

The guest, an ordinary person the audience has never heard of, has the chance to tell the company they are either misrepresenting a personal event or that they are dead-on.

Guests who are the focus of each Lifegame will be selected by a coordinator. Some of the guests will be solicited via a web site. They are not paid, but there is a parting gift and hospitality.

McDermott said that in the brief screening process, done days in advance, coordinators try to get a range of people.

"It's great to have people who have done very creative things, but it's good to have people who have ordinary lives that people can relate to," he said.

Lifegame does not seek people under 30 to be guests, however, "mainly because people over 30 have lived a bit and they can look at their past with a little bit of awareness."

And the evenings are not pre-determined.

"We don't [meet] them until about an hour and half before the show," McDermott said. "We meet them for 20 minutes and show them what kinds of things we might do in the show, what kind of games," he said. "It doesn't help to know anything before the show. What makes it work is that it's spontaneous. If you do know stuff, it can get in the way."

The improvisational show was first presented at The Brewery Arts Centre in Kendall, England, and then the Lyric Hammersmith in London. Audiences at the La Jolla Playhouse ate up performances there earlier this summer.

Is it therapeutic for the guest and the audience?

"If it is, it's a happy byproduct," he said. "If theatre is good theatre, it is going to be therapeutic anyway. Storytelling by its nature is therapeutic. But it's not like 'therapy.'"

McDermott said it wasn't uncommon to see audiences crying out of recognition, and talking after the show about their own experiences.

"It does make people examine their lives, I think," he said.

Sometimes, the performers are surprised by the candor and weight of the stories they hear.

"People come on the show and say they haven't had interesting lives and their small turning points turn out to be epic," he said. "There were more than a couple people who told big stories: A woman who told a story about her abusive childhood and how she wanted her daughter to have a different experience. She tells that story publicly, and it becomes a story that is part of the community."

Is it raucous? Wild? Shocking?

"It's actually a very gentle show, it's like spending a gentle couple of hours with someone and having a personable chat with them," McDermott said. "What we like about it is that it's not just laughs, although the show is funny. But it's funny out of recognition rather than lampooning people."

Lifegame is presented by David Stone, Dan Markley, Nina Essman and Julian Schlossberg.

The company includes Niall Ashdown, Angela Clerkin, Crouch, Guy Dartnell, Stella Duffy, McDermott, Toby Park and Simpson.

Tickets are $25-$37.50. Jane Street Theatre is at 113 Jane Street in the Hotel Riverview at the West Side Highway. For tickets, call (212) 239 6200.

-- By Kenneth Jones