What's new on TV this fall. You can expect more drama and action-adventure, a dollop of new comedy, and a return to the variety format with the indomitable Dolly Parton.

WHAT'S that? You're tired of ``Cheers'' and ``Newhart'' reruns - good as they are? And other reruns - bad as they are? You say you're ready for new material? Take heart (I think). It's coming.

How about a hopeful comic and a free-wheeling rock-music lover helping a widowed father raise his two small daughters? What about a figure from a cartoon who crosses into the real world - well, the prime-time version of the real world. Or a formal New England professor who finds himself running a New Orleans diner. Or - and this may be the topper - a half-human creature who periodically races through tunnels beneath New York City to save an ex-socialite lawyer from bad guys.

Yes, the Big Three networks' fall season looms, though not all of it as outlandishly as these formats suggest. Many series fall comfortably - perhaps too comfortably - into the comedy and action-adventure types you know so well. And most of the formats - from derivative to hoked-up to interesting - have the telltale ``maybe-this-will-work'' feel to them, as they vie for viewership at a time when network TV itself faces stiffening competition from cable, syndication, home video, the fledgling Fox Broadcasting Company, and other sources.

Although several shows start their regular runs the week of Sept. 21, lots of expanded ``previews'' as well as late-starters have fractured the notion of a traditional starting week. In brief:

Twenty-two regular new series will premi`ere, representing something over a quarter of the prime-time schedule: nine on CBS, eight on ABC, and only five on NBC, which, as last year's ratings king, is least eager to fool with the winning combination of its current schedule.

Just under half the prime-time schedule will be reshuffled.

``Drama'' - a generic term including action-adventure - remains the biggest category (particularly police shows, which are up significantly this year).

Comedy shows, the second biggest category, are also up this year, even though fewer new comedies are being introduced this season than last. Male characters will be more visible in these comedy formats, often as part of an unconventionally structured family unit.

The premi`ere of ABC's ``Dolly,'' starring Dolly Parton, marks the first time a network has attempted a weekly variety show since another country-music star - Barbara Mandrell - left the air five years ago.

The new shows (see times on complete schedule, next page):

Sunday

My Two Dads (NBC): An example of the untraditional-family theme. Two men of opposite type - a yuppie and an artist - share the upbringing of a 12-year-old girl. The question of just which one is the biological father is part of the format.

Dolly (ABC): Country star Dolly Parton spearheads the return of the weekly variety format, with music, dance, comedy, and celebrity spots.

Buck James (ABC): Dennis Weaver plays a slightly renegade surgeon, a cowboy at heart, who fights red tape and conformity inside and outside the Texas hospital where he works.

Monday

Everything's Relative (CBS): Two brothers - one an introverted grind, the other a high liver - form yet another variation on TV's ``contrasting-characters'' format. Anne Jackson plays their mother.

Tuesday

Jake and the Fatman (CBS): William Conrad is a tough California district attorney, and his undercover investigator is a luxury-loving young man whose style - you guessed it - contrasts sharply with his boss's.

J.J. Starbuck (NBC): Dale Robertson has the role of a wealthy, unconventional Texan, who travels the country in a Continental convertible adorned with steer horns, helping people in trouble.

The Law and Harry McGraw (CBS): Jerry Orbach stars as a Boston private eye in a cheap suit - he's often been seen on ``Murder, She Wrote'' - who's a nice guy under the brash exterior.

Thirtysomething (ABC): This brooding, socially conscious study centers on a suburban couple who face the realities of reconciling a family and two careers.

Wednesday

The Oldest Rookie (CBS): A middle-aged cop (Paul Sorvino) leaves his desk job to pound a beat again, finding himself an aging ``rookie'' working with a young - and difficult - ``veteran.''

Hooperman (ABC): In this comedy-drama, John Ritter puts his considerable talents to work as a San Francisco cop who inherits an apartment building and has to juggle the two responsibilities.

A Year in the Life (NBC): Extension of an acclaimed six-hour miniseries about three generations of the Gardner family living together in Seattle and facing a realistic variety of life's problems.

The Slap Maxwell Story (ABC): Dabney Coleman is an outpsoken, somewhat bullheaded sportswriter with an estranged wife (Susan Anspach), and a girlfriend.

Thursday

Tour of Duty (CBS): TV version of the classic military format - in the late '60s, a mixed bag of recruits learn to live and fight together in Vietnam.

A Different World (NBC): ``Cosby Show'' spinoff, with daughter Denise Huxtable going off to college and living on her own. Look for ratings-booster visits from her parents.

Wise Guy (CBS): A federal agent takes on undercover role of a street punk in this story of a cop's efforts to battle organized crime.

Friday

Full House (ABC): A widower recruits a would-be comic and a rock-loving free spirit to help him raise their two little girls.

Beauty and the Beast (CBS): A strange creature (human?) lives under the New York streets and travels through them to save a woman he had previously rescued, and who now works for, a district attorney.

I Married Dora (ABC): An American widower hires a Salvadoran housekeeper to look after his two children - then marries her when she is faced with deportation.

Private Eye (NBC): Laid in the '50s, this action series features an ex-cop who takes over his murdered brother's Los Angeles detective agency.

Saturday

Frank's Place (CBS): An uptight college professor (Tim Reid) finds himself running a New Orleans diner - and dealing with a variety of types he's never met before.

Once a Hero (ABC): A comic-book figure comes to life and battles the forces of evil in the real world.

Leg Work (CBS): A New York private eye fights crime - and the bill collectors - with the unofficial help of some well-connected friends.

On this slate, police dramas are on the rise, while comedies seem to be waning a bit.

``About three or four years ago the general wisdom was that the situation comedy was dead and buried,'' notes Betsy Frank, a vice-president of the New York advertising agency Saatchi & Saatchi DFS Compton. Then came the huge success of ``The Cosby Show,'' and comedy came to life again. ``Last year was probably the high-water mark for situation comedies,'' said Ms. Frank by phone. ``And then too many of them started to fail.... So now we see an overlapping trend: You still wind up with more comedies on the air, because you have some established ones that are still working. But in terms of development, there seems to be greater emphasis on the dramatic category.''

The new schedule also shows some of the effects of a wild card in the ratings game. It's called the ``people meter'' a new, electronic method of recording viewers. '' The new device - which has been having some start-up problems - tends to give more weight to younger and more male-dominated segments of the audience than the older ``diary method.''

Actually, the competition for a younger viewer profile has been going on for years. ``ABC had always been strong among the non-adult and young-adult audiences from the mid-70s on,'' Ms. Frank observes. That dominance was challenged a few years ago by ``The Cosby Show.'' This year, ABC is contining its strategy of trying to reach those viewers at 8 o'clock, to narrow the gap with NBC.

``CBS, on the other hand, has had dreadful luck with comedies at 8 o'clock,'' says Ms. Frank. ``This year its strategy says: Leave the kids, the teens, the 18-to-34s, to ABC and NBC. Let them fight it out for that group, and we will go after a more adult audience, and particularly a more male audience at 8 o'clock.'' CBS's strength is in the later evening hours, and now it hopes to develop that group early in prime time and then keep them through the evening.''

Yet TV audiences as a whole remain older than the national profile. So, as Ms. Frank points out, ``in spite of the new [ratings] technology, there's clearly going to be a conscious aim to reach the older viewers.