On May 3, CBS' Dallas will ride into the sunset, but its legacy is apparent in the abundance of special cliff-hanger episodes that fill May's TV schedule. The modern-day leave-'em-guessing season finale was almost nonexistent when J.R. Ewing was shot 11 years ago; now, it's as much a staple for sitcoms and dramas as it is for prime-time soaps. Highlights in the coming weeks:
* Amen The fifth season wraps up with a two-parter in which Thelma goes into labor with an assist from hardest-working-parolee-in-show-biz James Brown.
* Cheers Sam's obsession with Frasier and Lilith's baby leads him to want a Malone of his own but who'll be the mom? Watch for a surprise as the sitcom ends its ninth season.
* China Beach Seven new episodes of the nearly defunct war drama are left to air; summer should bring a moving finale reuniting McMurphy and her colleagues at the Vietnam Veterans Memorial in Washington, D.C.
* Dallas This is the end: Episode 356 of the prime-time soap offers two hours of special appearances by long-departed Ewings, friends, and foes and asks what life (not to mention TV) would have been like had J.R. never been born.
* A Different World Graduation day sends some of the regulars off to postcollegiate life and pushes Dwayne and Whitley toward a moment of truth that will affect their romantic future.
* Evening Shade A two-part conclusion to the first season offers an appearance by Terry Bradshaw and the birth of Wood and Ava's baby.
* Knots Landing A two-hour episode will offer the series' specialty multiple intertwined cliff-hangers involving all of the cul-de-sac's residents and leave the life of at least one familiar face hanging in the balance.
* Midnight Caller In a three-hour story that could be the show's farewell, Killian meets a woman who may be his daughter and ventures among the homeless to solve a murder.
* Murphy Brown Murphy may be ready for romance in the third-season finale but is it with her ex-husband (yes, she really has one) or trash-TV king Jerry Gold? Series creator Diane English promises a shocker in the show's last 30 seconds, so watch closely.
* Night Court A two-part episode will bring a surprising change for Dan and romantic developments for Christine and Harry.
* Quantum Leap Newly lofty ratings have guaranteed that Leap will return next fall, but this season's big finish, in which Sam is trapped in the body and mind of a psychiatric patient undergoing shock therapy, should still generate some suspense.
* thirtysomething With the show's return next season still in doubt, May's episodes will be particularly compelling; watch for new career opportunities for Melissa and major upheavals in Michael's job and marriage.
* Twin Peaks In a two-hour special, Dale Cooper and renegade former FBI agent Windom Earle engage the town in their final good-versus-evil showdown, with the prognosis for several Peaks residents and the series looking bleak.