Murder, She Says : TV: The grind of a weekly hour series is too much, but a half-hour show is something else.

At the end of this season, Jessica Fletcher is leaving. And this time, she’s not coming back.

Of course, Angela Lansbury--who has portrayed her in the CBS mystery series “Murder, She Wrote”--has said that before. But CBS panicked at the thought of losing one of its few hits and wooed her back with promises of shorter working hours, new movies and miniseries to suit her talents, and a splashy 1989 Valentine’s Day gala in her honor at the Biltmore.

But this time, Lansbury said in a recent interview at her Brentwood home, the network can’t beg hard enough, pay enough, or throw enough shrimp on the Biltmore buffet to persuade her to play Fletcher for another season.

“I wouldn’t be at all surprised (if CBS tried to talk her into another season of ‘Murder’),” Lansbury said evenly over a cup of mint tea in her airy living room. “But I can say right now that under no circumstances would I do it.

“It would be impossible, because the only way I would be able to do another season is to do the same workload, and I just can’t do it anymore. I think I’d go mad.

“It’s just nose-to-the-grindstone work. They’ve tried. They’ve tried to wean me out of some scenes now, and I do have my Fridays off now, which has helped me tremendously. . . . It was 14, 15 hours a day. I was going to have a physical breakdown, I didn’t get enough sleep, I didn’t have enough time to get my own act together.”

CBS has assured Lansbury that she won’t have to go away angry. The network has made a deal with her company, Corymore Productions, to develop a half-hour show for the fall of 1991, in which she would star. It is slated for the same 8 p.m. Sunday time slot in which “Murder, She Wrote” is spending its seventh year.

“They (CBS) want me to stay in my time slot,” Lansbury said. “They love the idea of me doing a half hour. They know who they will put in front of me, and I think they know who they are going to put behind me. That’s an enviable position to be in, but it’s also pretty frightening.”

While remaining mysterious about the show’s content, Lansbury refuses to invoke the word sitcom , describing the three-camera series as a “light entertainment” that will allow her to use some of the theatrical talents that put her name in lights on Broadway in numerous shows, including “Mame,” “Gypsy” and “Sweeney Todd.”

Most important, the new show “will cut my workload by half--maybe even three-quarters,” Lansbury said. “It will be a light entertainment with a tremendous amount of humanity and music and humor and all kinds of things. In other words, I’m going to get a chance to use some of the skills that I have up my sleeve but haven’t used on television.

“I really love television. People say to me, ‘Come back to the theater’--and I’d love to for a limited shot. But I don’t want to do a long, long run on Broadway again. It’s too disruptive to life. . . . Anyway, I’ve fallen in love with a major audience, which is the TV audience.”

While content with her new CBS deal, Lansbury acknowledges that the network has not been successful in finding attractive movie or miniseries scripts for her. Last season found her network-hopping to ABC in the “The Shell Seekers”; now she is starring in NBC’s “The Love She Sought,” which will air Sunday at 8 p.m.

“The Love She Sought,” filmed on location in Dublin, is based on Jon Hassler’s novel “A Green Journey.” Lansbury plays Agatha McGee, a stalwart Catholic school instructor who pins her hopes for love on an overseas correspondence with a man she has never met.

“Actors have a terrible time these days finding good material,” she said. “Actresses like me, you know--I’m not going to say of a certain age . I haven’t had any problem myself, really . . . but when something presents itself, you don’t just walk away.

“If you love acting, you want to act somebody different for a change--it’s as simple as that,” she continued. “It’s getting away from the tried and true, and the tried and true for me has been Jessica Fletcher. I’ve played her for seven years. I love her dearly, but I had to get away from her certainties , do you know what I mean? With Agatha, I had an empty vessel to fill.”

Empty vessel or not, McGee has some definite Fletcheresque qualities: Both characters stride through life with stout heart, unbending morals and a good pair of garden shears. Lansbury said that, while she craves variety, she will continue to portray upstanding women. She wants the TV audience to like her.

“Jessica Fletcher has an effect on people. If there are people like her around, God’s in his heaven and all’s right with the world,” she said. “This is very comforting in a world where every hour brings shock, sadness and disruption. These little plots are like crossword puzzles, and she’s going to put everything right.

“In this year, 1990, I wouldn’t play an evil woman. It’s awfully hard to get away from playing an evil person; it takes many years to live it down. . . . I’ve turned down playing evil women recently--very, very good parts, and they did not help the ladies who played them, let me tell you.

“I’ve done that gamut--and there are some great roles. But I think they belong in the theater, rather than on television.”

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