With a successful movie playing in theaters across the land and an Oscar nomination behind him, it was time for Howard E. Rollins Jr. to take a walk on the wild side. It was time for him to try his hand at series television, where the only thing worse than being canceled overnight is to never be canceled at all. Series TV, where the odds against going to heaven are something like 6 to 1.

"It's a very new feeling, to say the least," said Rollins. "But it's such a different kind of show, I think I can handle it."

The show is "Wildside," a Disney production for ABC that promises to be fresh and old at the same time. The freshness is in the faces it will bring to television each Thursday night, Rollins' among them, and the offbeat premise of the show. Bu it's also a western, one of the oldest TV and movie formats, so old that until recently even Clint Eastwood quit making them. But therein lies still more freshness.

"They're one of the strongest genres on television and films," said Rollins. "There's been a complete absence in recent years. I think people are ready to see that kind of thing. I think there's whole a generation of youngsters who are ready for something beyond Pac-Man.

"This is not a typical macho western," added Rollins, a Baltimorean who left Towson State College in his sophomore year to act. "It has realistic people. It's got a modern feel to it in terms of the way the characters are structured."

Thumbnail sketches of the characters make an interesting rogues' gallery. The series deals with a group of semi- reformed rough-riders of the 1880s who are ordinary citizens of Wildside County -- until trouble starts in the territory. When the governor calls on them with a problem, they become an elite law enforcment group, sort of like "The Wild Wild West" meeting "Little House on the Prairie." The cast of characters is an ethnic feast of fun names:

Rollins plays Bannister Sparks, proprietor of Bannister's Emporium & Trading Company -- "it's like a tiny Woodies." He's also an explosives expert.

William Smith is Brodie Hollister, a horse rancher with a reputation as the fastest gun in the West and 29 notches on his Colt to back it up.

J. Eddie Peck is Hollister's son, Sutton. He helps out on the ranch and is none too shoddy with a six-gun himself.

John DiAquino plays Varges De La Cosa, a crack gunsmith who refuses to use one. Knives and bolos are his thing.

And there's Terry Funk as Prometheus Jones, an overgrown vegetarian who handles all the rope work.

Oh, yes. The show also has a girl or two (Meg Ryan as Cally Oaks, editor of the Wildside Daily Flash, and Robin Hoff as Alice Freeze, the undertaker) and a kid, Jason Hervey as Zeke, a 14-year-old budding mercenary. Sandy cPeak is Gov. J. Wendell Summerhayes.

"It all opens up a cornucopia of possibilities for character development," said Rollins.

That's what they've said about Rollins' career development too, after he won an Oscar nomination for "Ragtime" and starred in "A Soldier's Story."

"I was very pleased that 'A Soldier's Story' succeeded," he said. "The movie was bounced from studio to studio. I know part of the reason was the question, how could a film with five or six black leads make money? And it did.

"I think it helped me establish myself as a bankable personality," he said.

But will the success of "A Soldier's Story" lead to more shows dominated by black casts and racial themes? "We'll have to wait and see," said Rollins. "It didn't happen on television with 'Roots.'>" So far, with "Soldier's Story," "there's been no tidal wave."

The same is true of Rollins' career. "There's been no dam-burst of work," he said.

Should the dam develop cracks, the "Wildside" shooting schedule would leave Rollins time to plug them. With his options seemingly open, he doesn't worry about the twin curses of series television -- early mortality and its stigma of failure and prolonged success and its attendant type-casting. He spoke with the optimism of an actor on location. "I take work," he said, "where there's something to do."