NOW THAT "Return of the Jedi," the final installment of the "Star Wars" trilogy, has shot into commercial hyperspace, what are the likeliest second-magnitude hits that may emerge from its towering shadow?

Adventure spectacles and comedies predominate during the summer months, when the movie business accumulates about 35 percent of its annual revenue, and this summer Hollywood is placing an outrageous number of eggs in the comedy basket: two dozen of the four dozen tentatively scheduled attractions. If the thought of all this hilarity alarms you, remember that half a dozen titles are already in circulation. Among this early-bird group only the French import "The Gift" contrives to finesse its defects agreeably, leaving "Still Smokin'," "Doctor Detroit," "My Tutor," "Joysticks" and Steve Martin's brainless "Man With Two Brains" to create an instant excess of dismal comedies.

The law of averages favors a few happy surprises from the remaining humorous resources: Eddie Murphy and Dan Aykroyd in "Trading Places," Richard Pryor in "Superman III," Chevy Chase and John Candy in "National Lampoon's Vacation," Robin Williams and Walter Matthau in "The Survivors," Rodney Dangerfield in "Easy Money," Jackie Gleason as a split personality in "Smokey Is the Bandit," newcomer Ted Wass as the successor to Inspector Clouseau--a bumbling New York policeman named Clifton Sleigh--in "The Curse of the Pink Panther," the SCTV trio of John Candy, Joe Flaherty and Eugene Levy in "Going Berserk" and the SCTV duo of Rick Moranis and Dave Thomas in "Strange Brew."

One of the strange aspects of this summer's comedy brew is the absence of Bill Murray, who seems to be the only prominent male comedian without a vehicle. Woody Allen has completed two new comedies of some kind, "Zelag" and "Broadway Danny Rose," but neither has been given a summer go-ahead. Another conspicuous oddity: the lack of even costarring parity for comic actresses. Only three seem to have theoretically leading roles to play--Teri Garr, costar with Michael Keaton in "Mr. Mom," which may be postponed until fall or winter, anyway; Loni Anderson, consort to Burt Reynolds in a car-racing farce called (ugh) "Stroker Ace"; and long-time-no-see Madeline Kahn, the wench among a flock of mock-pirates and aristocrats (including Graham Chapman, Eric Idle, John Cleese, Peter Cook, Marty Feldman, Peter Boyle and Cheech & Chong) recruited for the spoof swashbuckler "Yellowbeard." Of course, Jamie Lee Curtis and Beverly D'Angelo might turn out to be adorable comic revelations in "Trading Places" and "National Lampoon's Vacation," respectively, and the marvelous Andrea Martin might have been ingeniously deployed as the secret weapon of "Going Berserk," but I'll believe it when I see it.

In theory "Private School" is a comedy vehicle for young actresses, notably Phoebe Cates, fondly remembered for "Fast Times at Ridgemont High" and mercifully forgotten for "Paradise," but it sounds dubious to me. Jacqueline Bisset continues to trifle erotically with the younger generation in what may be the boys' version of "Private School," a sex comedy called "Class." Newcomer Andrew McCarthy plays a prep school student who lucks into seduction Bisset-style, since she's his roomie's impulsive mom. Maybe writer-director Lewis J. Carlino should have called it "The Undergraduate."

Moviegoers who don't get to things promptly should also be reminded that Bill Forsyth's wonderful "Local Hero," the year's best comedy so far, will still be around this summer.

Not that all the comedies loom as strictly kick-in-the-pants or gross-you-out inanities. The trailer for John Landis' "Trading Places" promises an entertainment with plenty on the ball: two troublemaking old tycoons played by Ralph Bellamy and Don Ameche conspire to settle a bet by forcing a fussy young colleague, Dan Aykroyd, to switch identities with a keen-witted young street hustler, Eddie Murphy. The prospect of Robin Williams and Walter Matthau as students in a survivalist course also earns a large benefit of the doubt for "The Survivors," which marks the return of director Michael Ritchie to social comedy, his strong suit. The premise of "National Lampoon's Vacation" certainly seems rich in comic potential. Is any real-life misadventure more common than the messed-up family vacation? It's also possible that something humorously fresh and authentic may emerge from the sleepers in the pack, perhaps "Risky Business," the first feature directed by screenwriter Paul Brickman, who wrote "Citizens Band." Can't Hear the Music

The curious absence of new musicals may not seem such a loss when you recall that last summer's quartet was less than triumphant--"Annie" and "The Best Little Whorehouse in Texas" were supplemented by "Grease 2" and "The Pirate Movie." But wait: "Staying Alive," Sylvester Stallone's sequel to "Saturday Night Live," depicts the trials and tribulations of dancers competing for roles in a new Broadway musical, so it may qualify as a semimusical. Cast as Tony Manero six years after leaving Bay Ridge, John Travolta is a struggling dancer aiming for stardom in the show. Between workouts he must try to resolve conflicting attractions to a pair of chorus girls.

Last summer's musicals weren't remotely as satisfying as this spring's delightful production of "The Pirates of Penzance," and there's a good original musical still playing--the cheerful, racy, energetic Australian import, "Starstruck," an open-ended holdover at the Key. In addition, an exemplary operatic film, the Franco Zeffirelli production of "La Traviata," appears solid at the West End Circle for the summer. There even seem to be people who are pleased to confuse that feature-length fashion commercial, "Flashdance," with musical romance (perhaps, if the love affair is between you and your mirror . . .), and it figures to survive the season better than many of the actual summer releases. Thrill Bills

There's been a 50 percent drop in the number of horror and supernatural thrillers--eight last summer, four this summer. On paper the money attraction would appear to be "Jaws 3-D," contrived to exploit the rejuvenated popularity of the 3-D process with young moviegoers while getting at least one more season of alarm out of Bruce the Great White Shark, now threatening the staff (Dennis Quaid, Bess Armstrong, the Oscar-winning Louis Gossett Jr.) and sightseers at a newly opened Sea World complex in Florida. One of the intriguing supernatural entries, Douglas Trumbull's "Brainstorm," the production that remained unfinished when costar Natalie Wood died in a drowning accident, was set for a late summer opening that has now been postponed indefinitely.

Despite its even more tragic, haunted production history, the anthology feature "Twilight Zone--The Movie," composed of four tales of the supernatural, three adapted from the original Rod Serling TV series, looms as a probable hit. Evidently, the ill-fated episode written and directed by John Landis, with Vic Morrow as a racial bigot who becomes a victim of his prejudices, begins the collection. It may or may not disappoint audiences to learn that Steven Spielberg directed the relatively serene interlude, a lyrical vignette called "Kick the Can," with Scatman Crothers as a pensioner in search of rejuvenation. Joe Dante of "The Howling" was reponsible for "It's a Good Life" with Kathleen Quinlan, Patricia Barry and Nancy Cartwright, the story of a small town dominated by the whims of a child. George Miller of "The Road Warrior" directed what should be the fright classic of the set, "Nightmare at 20,000 Feet," with John Lithgow inheriting William Shatner's original role as a plane passenger driven to desperation by the sight (or delusion) of a gremlin on the wing.

When you add "Psycho II," which opened Friday, to the list, the horror bloc looks inescapably derivative. The only "original" is the movie version of Stephen King's "Cujo," not exactly the freshest prospect of terror in the history of the medium.

Among the adventure thrillers it may be easier for the sequels like "Superman III" and "Octopussy," the latest James Bond vehicle for Roger Moore, to hold their own with loyal publics while "Jedi" continues to generate revenue at a pace of $6.5 million a day. Presumably, comic elements will enhance both films. Cast as a comic villain--a computer genius in the hire of tycoon Robert Vaughn--Richard Pryor could supplant Christopher Reeve as the indispensable attraction of "Superman III." I can't bring myself to trust the intuitions of director Richard Lester and screenwriter David Newman with the Superman character. It seems to me that they undermined "Superman II" with decidedly nasty comic touches after cashing in on the enormous good will generated by the original. Somehow, I don't really expect a change of tone.

The problem for the Bond braintrust is to get the basic itinerary back in smooth working order after allowing so much slack to accumulate in "For Your Eyes Only." I'd anticipate a far more streamlined effort this time around. At least the film no longer faces head-to-head competition with the more attractive Bond project, Sean Connery's return in "Never Say Never Again," now postponed till October. A ludicrously lewd-sounding title (won't it look swell sharing a marquee with "Stroker Ace"?), "Octopussy" evidently refers to the femme fatale, Maud Adams as a fabulously wealthy beauty who maintains a palatial residence in India, runs a circus troupe and may traffic in both stolen gems and stolen government secrets.

The incorrigible Peter Hyams ("Outland," "Capricorn One") gets another crack at science-fiction adventure in something called "Star Chamber"; Paul LeMat, Nancy Allen, Diana Scarwid and Louise Fletcher get chased around by aliens in "Strange Invaders"; and a Conan clone called "Yor: The Hunter From the Future" turns up impersonated by Reb Brown in an obscure action potboiler shot in Turkey. Peter Yates appears to have a monopoly on medieval adventure fantasy with "Krull," which takes Ken Marshall of "Marco Polo" semi-fame on a quest for his kidnaped bride and could be as classy a production as "Dragonslayer."

It wasn't so long ago--the summer of 1975 to be precise--when the movie business marveled at the box-office performance of Spielberg's "Jaws," which generated and then sustained grosses of over $1 million a day at about 500 theaters. With the million-a-day barrier demolished, sights kept edging upward, and now "Jedi" has raised the ante to a level that diminishes even high-stakes competition.

When "Blue Thunder" was the national box-office leader two weeks ago, grossing about $11 million at more than 1,500 theaters in its opening week, exhibitors found this showing a slight disappointment. Since "Blue Thunder" declined 25 percent in its second week while losing the top spot to the 3-D curiosity "Spacehunter," and both these thrill-crazy attractions were predictably engulfed by last week's "Jedi" tidal wave, there's a certain nervousness in the business about the competitive chances of pictures scheduled to open in its wake. This weekend's trio--"The Man With Two Brains," "Psycho II" and the eminently exploitable doomsday thriller "WarGames"--might have anticipated a sporting chance at the box office, everything being equal. Now they'll have to hang in tenaciously to share stray beams of the limelight. Drama

The scarcity of dramatic features seems a nonsensical aspect of the season and allows disgruntled fans to exaggerate that there's nothing to see all summer long except juvenile entertainment. At worst it's a temporary inconvenience, since the ostensibly grown-up stuff is hoarded for fall release. Moreover, uniqueness can be commercially advantageous for the dramatic movies that buck the lightweight summer flow--for example, "Body Heat" two years ago and "An Officer and a Gentleman" and "The World According to Garp" last year. "Staying Alive" appears to be the only American picture that might generate a comparable appeal, but a pair of imports, the French period drama about a suspected case of imposture, "The Return of Martin Guerre," and Ingmar Bergman's nostalgic family chronicle, "Fanny and Alexander," set in a provincial Swedish town in the early 1900s, could take up the slack with moviegoers hungering for human-interest material.

The Bergman film looms as a very special occasion, in part because it may be his valedictory work but also because it seems to recall the period and seriocomic tone of his great boudoir comedy "Smiles of a Summer Night." Fanny, 8, and Alexander, 10, are the youngest children of a theatrical manager named Oscar Ekdahl and his wife, Emelie, the leading actress of the repertory company run by Oscar. Three hours long, the movie is evidently calculated to draw one into the secure domesticity of this prosperous, stimulating half-Jewish family of artists and businessmen and then follow the potentially calamitous consequences of a death in the family, particularly from the point of view of the children. Wouldn't it be gratifying to discover that Bergman had created the screen's newest sentimental masterpiece, the "E.T." of 1983?

A list of supposedly "confirmed" opening dates for the remaining summer releases may be useful, but remember to check the film ads and calendars frequently, since numerous changes are likely and some attractions still lack even tentative opening dates.

"Trading Places" (R) on June 8; "Octopussy" (PG) on June 10; "Fanny and Alexander" (R) and "Superman III" (PG) on June 17; and "The Survivors" (R), "Twilight Zone--The Movie" (PG), "Yellowbeard" (R) and "Porky's: The Day After" (PG) on June 24.

"Stroker Ace" (PG) on July 1 or 8; "Staying Alive" (PG), "Snow White and the Seven Dwarfs" (G) and possibly "Mr. Mom" (PG) on July 15; "National Lampoon's Vacation" (R), "Jaws 3-D" (PG), "Krull" (PG) and "Class" (R) on July 22; "Private School" (R) on July 29.

"The Curse of the Pink Panther" (PG), "Risky Business" (R), "Star Chamber" (PG), "Get Crazy" (R) and "Yor" (R) on Aug. 5; "Easy Money" (PG), "Smokey Is the Bandit" (PG), "Cujo" (R), "Kidco" (PG), "Savage Islands" (PG), "Going Berserk" (R) and "Strange Invaders" (R) on Aug. 12.