It's a secret fear in every artistic director's heart when making the decision to cast a star in a one-person show: What happens if the star can't go on?

Hartford Stage is facing this decision in the midst of Kate Mulgrew's vocal problems surrounding the demanding role of Katharine Hepburn in the bio-show "Tea at Five." The dilemma began early this week when several performances were postponed. But when there was a diagnosis of inflammation of the vocal cords and shows were being canceled with no hope of rescheduling, a more dramatic and permanent solution was needed.

Now, after consultation with both doctors for the theater and for the actress, Mulgrew will cut back her performances from eight to six a week.

"There were some dark hours this week," artistic director Michael Wilson said from New York, where he is overseeing previews of Eve Ensler's "Necessary Targets" and rehearsals for "The Carpetbagger's Children." Both Hartford Stage shows are opening in New York in the next few weeks. "The good news is that everyone wants to see her do this role. If we didn't have such an extraordinary demand, we wouldn't have such a problem right now."

The Hartford Stage should meet its projected income for the run of the show, even with fewer performances, because they are sold out. Box office sales were so strong right after the opening that Mulgrew agreed to an additional week, raising the projected number of performances from 35 to 42. Her new schedule calls for a total of 33 performances, stretched out to include the announced extra week.

There are also discussions being held with Mulgrew about more shows in the future, but nothing is definite, Wilson said. "But we're close to a solution," he said.

Although the script received mixed reviews, most critics hailed Mulgrew's performance as Hepburn at ages 31 and 76, with heavy praise for her interpretation of the older Connecticut icon.

When asked if he felt this was part of the "Hepburn curse," Wilson laughed.

"If this is a whiff of the Hepburn curse, " said Wilson, "it's that we're going to lick it. And just as Hepburn kept coming back - overcoming her accidents and illnesses, Kate Mulgrew is very resilient and the show will go on."

The potential loss of Hartford Stage's leading lady puts a spotlight on the practice of hiring understudies and the demands of one-person shows.

Regional theaters traditionally do not employ understudies for their shows, even in one-person shows. "It's just not in the budget because the runs are so short it doesn't justify the expense," Wilson said. (There were none for Jean Stapleton in "Eleanor" or David Selby in "St. Nicholas." TheaterWorks in Hartford, which often presents one-person shows - some with name actresses such as Valerie Harper and Tovah Feldshuh - also does not have understudies for its runs.)

"We've been very fortunate," says Steve Campo, artistic director of TheaterWorks, which is currently showing Harry Bouvy in a one-person show, "Fully Committed." Bouvy, who plays 38 characters in the show, developed vocal problems last week, but his situation was solved with vocal techniques designed to protect his voice in performance.

Campo said that when a show is on one person's shoulders, the pressures are more intense which, increases physical stress.

"Any time you're banking on a single person in a high-pressure situation where the stakes are high," Campo said, "it makes everything more problematic."

The loss of a leading actor in a play has plagued many theaters in high-profile situations recently. The opening of Edward Albee's new play, "The Occupant," was indefinitely postponed after star Anne Bancroft developed pneumonia. Her understudy, Kathleen Butler (who was in "Three Tall Women" at TheaterWorks) performed for some of the shows before the run was suspended until March 19. Nathan Lane began missing performances of "The Producers" because of vocal problems and his part was performed by Brad Oscar, who played a supporting role in the show (whose role, in turn, was played by another actor). Lane's schedule eventually was cut back from eight to six performances a week.

The Mulgrew saga began when the actress felt she could not perform on Tuesday night because of vocal problems and that show was rescheduled for Wednesday night. That allowed the actress to rest after a five-performance weekend and a flurry of promotional events.

But after Mulgrew performed Wednesday night, her throat problems persisted and Thursday's matinee was postponed to March 11 and the Thursday evening show was canceled.

After a vocal specialist in New York, who had worked with a range of performers such as Pavarotti, examined Mulgrew Thursday, it was decided that the actress needed a reduced schedule. Friday night and Sunday matinee performances were canceled.

Mulgrew will perform tonight at 8 and at 7:30 p.m. on Sunday. Mulgrew then will switch from an eight-performance to a six-performance week for the remainder of the run. There will be a performance Tuesday at 7:30 p.m., but Wednesday'sperformance will be canceled as part of the new schedule. Further changes to allow for a six-show weekly schedule will be announced shortly. The theater will directly contact all ticketholders with rescheduling or refund arrangements.