From the new season's miniseries -- a few plums

Innovation doesn't always pay off on TV. Lagging behind the two other commercial networks for the season to date is NBC, the most innovative of the Big Three networks this year, with a whole group of critically approved, low-rated series.

Last week, however, NBC perked up a bit to make the No. 1 Nielsen spot because of the World Series. Next week, NBC is depending upon a miniseries, Little Gloria . . . Happy at Last (Sunday, 9-11 p.m. and Monday 9-11), to perk things up even more. Based on the book by Barbara Goldsmith, this poignant tale of the struggle during the 1920s and '30s for custody of the poor little rich girl, Gloria Vanderbilt (and her millions), is peopled with superstars giving super performances.

Skillfully written by William Hanley and directed with subtlety by Waris Hussein, it is much more than a lurid history of a family battle. It is an authentically mounted sociological tract which details the mores of the period, the lust for money and power of a whole generation, the amorality and immorality that pervaded the society of the descendants of our ''robber barons.''

If it suffers a bit because the denouement is not totally satisfying, it is because such is often the case in real life. And producer Edgard Scherick has kept ''Little Gloria'' startlingly real. But don't be misled, it is also a jolly good show.

Meantime, on PBS, the new season is just beginning. Three interesting new miniseries premiere on Monday - ''The Magic of Dance,'' ''The Charterhouse of Parma'' (previewed in the Monitor's Oct. 20 issue), and ''Six Great Ideas.'' Fonteyn on dance

The Magic of Dance (PBS, for six Mondays starting Oct. 25, 9-10 p.m.) gives viewers an opportunity to perform a kind of electronic pas de deux. As Dame Margot Fonteyn explains it, the series is like ''casting a light over certain periods in time, picking out the high points and revealing some of the little-known details.'' And always there are surprises, because ''none of us can ever know everything about the magic of dance.''

In the series premiere, Dame Margot focuses on the rise of the male dancer, showing us film clips of Nureyev, the Dance Theater of Harlem, Sammy Davis Jr., and Fred Astaire. We are even treated to a filmed excerpt from ''Le Corsaire'' which she danced with Nureyev and an excerpt from ''Swan Lake'' danced by Natalia Makarova.

In later episodes there are clips of both Nureyev and Baryshnikov, Ivan Nagy, Roland Petit, Zizi Jeanmaire, Isadora Duncan, Ruth St. Denis, and many more. Dame Margot, a poised and informed dance enthusiast, does not pretend to be a dance historian. She merely tells us of the magic of dance as she has experienced it, as she has learned of it.

''Magic'' is really a free-flowing conversation about the dance, in which the delightful coolness of Fonteyn envelops everything. Her personal charm endows the film with that very same special quality. The viewer is allowed to experience movement with Dame Margot, to jette along with her through the history of dance, stopping here and there for a bow, a smile, the acceptance of a bouquet, a cast party.

Viewers who decide to join Dame Margot's magic party can be assured that they will never have a better invitation to the dance. Great ideas

Focus the camera on one provocative philosopher-teacher and one compassionate journalist-provocateur, and chances are you will end up with a thoroughly engaging incitement to thought. You will if they are Mortimer Adler and Bill Moyers, respectively, that is.

Six Great Ideas (PBS, six Mondays starting Oct. 25, 10-11 p.m.) is, perhaps, the supreme ''talking head'' show. Philosopher-teacher Mortimer Adler, who among other things conducts seminars at the Aspen Institute for Humanistic Studies, has teamed up with Bill Moyers, ''the conscience of American television,'' to explore six of the greatest philosophical concepts of Western civilization - truth, beauty, goodness, liberty, equality, and justice.

There are carefully edited candid film sequences of Aspen seminars with an amazingly able group of students. In among these sequences, Adler and Moyers wander through the beautiful Colorado countryside, clarifying, expanding, explaining, even at times obfuscating. But they will have you listening, thinking, and yearning to be able to break in and tell them just where you stand yourself.

''Six Great Ideas'' - which will undoubtedly be available on videocassettes for those who want to learn more about the world of ideas - is overflowing with the excitement of intellectual revelation, the dynamics of discovery, the thrill of insight. As Moyers says: ''The people who chanced the medium with us must pass a sign that reads, 'Beware of the terrible simplifiers.' Mortimer Adler is not afraid of such risks, and I've long admired him for the courage it takes to champion difficult thought in a popular form, where even the profound can appear superficial and the superficial profound.''

But Adler takes the risks in his seminars, in his life, and now on television , because, as he puts it, ''Everyone is called to one common, human vocation: that of being a good citizen and a thoughtful human being.''

The producer and director of ''Six Great Ideas'' is Wayne Ewing, but anybody familiar with Moyers can detect his hand and thought. ''Six Great Ideas'' is another landmark series in the television of entertainment/learning, a field in which Moyers excels. (The superb new series ''A Walk Through the Twentieth Century With Bill Moyers'' has not yet been placed elsewhere, now that CBS Cable is folding, by the way.)

Throughout the series, based in part upon Mr. Adler's book ''Six Great Ideas'' (Macmillan), viewers will find themselves questioning their own values, comparing them with Adler's, measuring them against Moyers's.

Don't expect ''Six Great Ideas'' to have you on the edge of your seat for every moment - there are stretches of boredom, segments of confusion, moments of annoying repetition. Taken as a whole, however, ''Six Great Ideas'' offers most viewers six of television's most stimulating hours ever. Le Carre thriller

George Smiley, also known as Max, is back on television.

John le Carre buffs who were taken with last year's ''Tinker, Tailor, Soldier , Spy'' miniseries on PBS may gorge themselves on the further adventures of le Carre's quintessential supersleuth, George Smiley, in a new six-hour spy melodrama, Smiley's People (aired on more than 100 stations, starting in some cities Oct. 25, others Nov. 1; check local listings for stations, days, and times).

As in the previous ''Tinker,'' Smiley is underplayed with utterly devastating restraint by Alec Guinness. Also as in the previous le Carre, the story line is so complex and full of twists and turns that the viewer has to watch and listen very carefully to make certain all the words and nuances connect.

''Smiley's People,'' produced by BBC/Paramount Films for Operation Prime Time , scripted by le Carre himself with John Hopkins, and directed by Simon Langton, has the now-retired Smiley forced to return to the ''Circus,'' England's counterintelligence agency, to do battle once again with his old Russian counterpart, Karla.

''Smiley's People'' is overloaded with fast-moving, subtle dialogue, hard to retain over a period of evenings, acted with laid-back subtlety by a cast full of superb actors like Guinness, Curd Jurgens, Eileen Atkins, Michael Gough, Beryl Reid, and Sian Phillips.

Smiley and the Circus have become underground cult figures, so success for the miniseries is foreordained, even though some of the facts may slip through your TV screen unencumbered by understanding.

By far the major bit of conversation among those watching is bound to be: ''Did you catch what he said?'' But never mind, it's all part of the le Carre one-upman game of sophisticated spymanship.