Presumably the title of George F. Walker's comedy at the young Caravan Theatre, "Risk Everything," is in the imperative. That's certainly the mode of its most distinctive character, Carol, a feisty con artist in middle age who rants repeatedly about going for broke -- especially when it's others who'll pay the price.

In other words, she's an enigmatic handful, with a zest for life, sex and risk that can be tonic, in spite of how she uses and abuses others, especially her frantic daughter, Denise. Carol has somehow parlayed a mobster's $35,000 into (we eventually learn) $68,000, and as the play begins, she's been badly beaten up, with worse threatened. But she's still trying to keep it all, lying to friend and foe, especially Denise, her distracted daughter.

The 90-minute play is set in the late '80s in a big city motel where Carol is holed up while others come and go and the situation worsens. Each revelation is another lie or partial truth, so we're as much in the dark as Denise, not to mention the two men who do the women's bidding -- Denise's comically hapless mate, R.J., and Carol's pick-up of the day, a perky older pornographer named Michael.

As events unspool, first one man and then the other returns under a comic-book-like threat of death. I can't be specific, but it's surprisingly funny. So is the whole play. As directed by John Gresh, it mixes comic heist caper with a touch of urban noir and incursions of farce.

With such a mixture, the title also describes the play, which wants also to be a serious tale of family dysfunction but feels sort of like a Sam Shepard urban desperado fable on laughing gas.

Or should. Director Gresh and Sharon Brady, in the pivotal, mood-controlling role of Carol, don't quite pull it off. The pathos in the story doesn't ring any truer than the occasionally forced goofiness. There's too much acting.

Possibly this is Walker's fault for mixing contrary ingredients without providing us with a strong enough need to care. But the actors share some responsibility. A more inspired Carol might give the play a clearer center. Heaven knows Brady works diligently, but there needs to be a further leap of grim reality or lunacy, probably both.

You can't fault hard-working Dana Hardy, whose Denise is caught in the middle, trying to take care of a mother who resists and a man who, though happy to be cared for, rather thinks he ought to show some spunk, even though he hardly has any. Ditto the middle-aged pickup.

Hardy has the thankless job of whining constantly, but she does it well and believably, and anyway, we'd like to whine at Carol, too. As R.J., Tony Bingham pushes too much toward comic caricature, or maybe he just can't find the reality in his character. I'm not sure there is much: Michael seems largely a comic goofball, and only Walker could fix that.

Comic goofball describes pornographer Michael, too, but Mark Conway Thompson wisely treats him with some restraint, creating a delightful comic miniature.

As you can see, these shiftless comic grifters aren't exactly cafe society. Our heart goes out to Denise. But what admiration we have goes to Carol, manipulative, selfish and infuriating as she is, because without her quirky risk-taking, there'd be no play.

I've counted myself a fan of Walker, a prolific Canadian. But I realize that rests only on his ambitious comedy of urban protest, "Love and Anger," which I reviewed in Toronto in 1989 and here at the Upstairs Theater in 1993, and his "Escape from Happiness," at CMU in 1994. While I subscribe to Samuel Johnson's view that there's value in adding to "the public stock of harmless pleasure," I thought that Walker had much more to him than that. On the basis of this "Risk Everything," I'm not so sure.

But any second production is a big step for a small new company like Caravan, which aims to use Equity actors in entertaining contemporary plays with some heft. More power to them.