It's not easy being Thomas Magnum, TV shamus. Each week there are bad guys, flying fists, gunplay and, even more scary, the competition—top-ranked Cosby over on NBC. In this, Magnum's seventh and some say last season, CBS finally relented and moved the 48th-ranked show to a new time slot. Opposite sixth-ranked Dynasty on ABC.

But Magnum is one tough dude. He won't go gentle into that video goodnight and, in fact, he still has some pretty slick moves to trot out. Like, for instance, Cynthia Farrell (Dana Delany), the luscious lady lawyer. Magnum meets her—and falls for her—on the show's two-hour premiere on Oct. 1. She's something special.

"Thomas has had a few flings and a couple of romances," explains Magnum, P.I.'s director, Alan J. Levi. "But this is more a relationship than a romance. They fall in love. He proposes—and she turns him down."

Not for long, or so the betting goes. Delany, 30, recently played the role of the lethal sexpot and former girlfriend of Bruce Willis on Moonlighting. "I already knew Bruce from his days as a bartender at the Cafe Central," she says, referring to a now defunct New York hangout for young actors on the make. "The wife of Magnum's producer spotted me in that episode, and I was cast without a screen test." In her Cafe Central days, Delany had played roles as diverse as Hayley Wilson in As the World Turns and the lead in the off-Broadway drama Blood Moon—certainly one of the least palatable parts in the American theater. "I played an innocent girl who is raped by her uncle's best friend," she says, "then self-aborts the fetus, cooks it into some pasta and feeds it to her uncle and the rapist."

Heiress to the Delany Flush Valve fortune—"There's a Delany flush valve in every toilet without a tank," she declares—Dana grew up in Stamford, Conn., Charlottesville, Va. and boarding school (Andover). Later she attended Wesleyan and then studied with New York acting coach Gina Barnett. In the same bar where she met Willis she also met actor Treat (Prince of the City) Williams. Although the two were "serious," that relationship broke up two years ago. "I don't think actors should get involved with other actors," says Dana. "You always say you won't become competitive, but you do." Still, she adds, "Treat and I are friends. In fact, we just talked on the phone today."

Back on the Magnum set, rumor has it that Dana will soon be returning for another episode. And when pressed, a CBS spokesman admits that, yes, "there may be a wedding in store for Magnum this season."

Presumably by then, Dana Delany will be flush with her new success. But will Magnum beat out Dynasty?