When the young Katharine Hepburn is asked whether she wants to be an actress or a star, Hepburn, or so the story goes, wastes no time proclaiming she wants to be a star.

And a star Hepburn continues to be, in a dazzling, dead-on portrayal of the four-time Oscar winner by Kate Mulgrew at Hartford Stage.

This one-woman show could very well be Broadway-bound. Even before Thursday's opening night, the 35-performance run was sold out. The theater has since tacked on another week of shows, but don't count on tickets hanging around for long.

That Tea at Five is taking Hartford by storm should come as no surprise. Here's a play about a local legend written by a native son, 35-year-old Matthew Lombardo, who has penned several off-Broadway scripts and written for the soaps.

The play is set in Hepburn's posh family estate in the Fenwick section of Old Saybrook, the place she would retreat when her career was on the skids and where the 94-year-old actress lives today.

Hepburn is always a big box-office draw, even now in her dotage. But she seems to be especially fascinating in her hometown of Hartford. During intermission, one fan could be heard dickering over details in the set. That's just wrong, he kept insisting.

Local interest aside, the play is a tour de force that should have legs no matter where it travels. In large part that has to do with Hepburn, feisty, enigmatic, a woman who never failed to speak her mind.

On musicals, her character dubs them a ridiculous art form."

"The only people I know who break into song every ten minutes are committed," she said.

On John Barrymore: "He became a father figure to me - in a grotesque sort of way."

But it wasn't Hepburn who intrigued playwright Lombardo as much as Mulgrew, who seemed to just be waiting to be cast in a play about the aloof, imperious actress. His instincts were sound.

With those classic Bryn Mawr looks and pinched, nasal-y twang, Mulgrew cuts a striking resemblance. With a little tweaking, the likeness is uncanny, especially when Mulgrew plays the aged Hepburn chronic tremor, wobbly diction and all.

Lombardo has chosen a couple of days from Hepburn's long, rich life a September afternoon on the eve of the 1938 hurricane, and a snowy day in February 1983, as she's nursing a broken ankle suffered when she drove her car into a telephone pole.

Whether by design or not, Lombardo paints the young Hepburn as shallow and self-involved, concerned only about her reviews and her next role. She has returned to Fenwick to lick her wounds after a string of film flops, and she's not the sort of lady with whom you'd want to share an afternoon tea.

When she's not snapping at her agent on the phone about how she was born to play Scarlett O'Hara, Mulgrew's Hepburn waltzes about the set, spouting lines with irritating histrionics.

This may be a faithful portrait of Hepburn in the '30s, but it's hard to take. She's a caricature of the Hepburn we know from her many films, not a person we can warm up to.

All that changes after intermission, though, as we share tea with an older reflective Hepburn, who weeps over the suicide of her 15- year-old brother, rages against her unfeeling physician father, and tries to explain her three-decade affair with "Spence."

Life is about choices, Mulgrew sighs. But would she change any of it? No way, she declares, in slightly spicier language. Life is to be enjoyed, she says defiantly. "What fun!"

It's this kind of resiliency that makes her character so endearing. At one point, Mulgrew seems as though she's going to collapse under the heartache of her life. She seems on verge of a profound confession, as she stammers, "I ... I ..." But it's only a silly admission: "I did a musical once, even though I couldn't sing or dance."

It's a marvelous moment, when the mood of the scene turned on a single phrase, where emotional clouds were swept away by a magical twinkle.

Tea at Five could have easily been a throw-away script that relied on its larger-than-life subject to fill seats. But Lombardo, who has never met Hepburn, obviously spent a lot of time thinking about what makes Hepburn tick.

And Mulgrew has a lot more depth than we might have guessed from her previous roles as a TV detective and starship captain. She may be guilty of overacting as the vain Hollywood starlet, but she gives a compelling, loving portrayal of the reclusive, sometimes irascible Hepburn of today.

Opening night, she also managed to deftly defuse an awkward moment. While reminiscing about the tragedies in her life, Mulgrew takes solace in the fact that time is the "great leveler."

She then walks to the fireplace to look at a family photo, only to have the mantle crash to the floor.

"Time levels other things as well," she quipped, as a packed house roared.

Tea at Five runs through March 17 at Hartford Stage, 50 Church St., Tickets range from $40-$60, but aren't expected to last long. On- line purchases are suggested at www.hartfordstage.org. Otherwise call (860) 527-5151.