Summer comes earlier every year, Hollywood Blockbuster Time.

Not content to begin the summer movie sweepstakes on Memorial Day weekend, major movie studios have been kicking off the season in mid-May for the past few years.This time around, however, it's early May - very early May.

The action sequel "FX 2: The Deadly Art of Illusion," which is thought to be a possible hit that could play through the early summer months, opened Friday, May 10, along with the celestial sex-change comedy "Switch," which has been playing in the larger urban centers for a couple of weeks.

Next Friday, May 17, Madonna's concert-documentary film "Truth or Dare" will begin what is expected to be a long run into the summer.

Then, as the Memorial Day weekend begins, we'll get a slew of potential hits, officially ushering in what is each year's most profitable moviegoing period.

Of course, if you talk to people representing the studios, all the summer films are potential blockbusters. But experience tells us that many of those scheduled are bound to bomb - some more explosively than others.

The movies to beat are "Robin Hood: Prince of Thieves," starring Kevin Costner, which opens June 14, and "Terminator 2: Judgment Day," with Arnold Schwarzenegger back as a deadly cyborg on July 3.

In the case of "Terminator 2," the anticipation factor has as much to do with its built-in audience as the presence of Schwarzenegger. Fans of the first film know that writer-director James Cameron has yet to let sci-fi action fans down, having proved his stuff with "The Terminator," "Aliens" and "The Abyss."

But "Robin Hood" looks hot because, in addition to capitalizing on Costner's presence, the studio has cleverly raised audience awareness with a thrilling preview trailer that has been playing in theaters for the past couple of months - it makes the movie look like "Raiders of Sherwood Forest."

Which movies will sneak out of thepack to challenge "Robin Hood" and "Terminator 2"? Who knows? But there probably will be another "Ghost" this year.

You might want to get some friends together, peruse the list and start an office pool.

Here are the candidates, complete with opening dates - dates that will undoubtedly change many times in the weeks ahead:

MAY

Cadence - Martin Sheen directed son Charlie in this look at racism in the military.

Impromptu - Judy Davis is George Sand, here pursuing Frederic Chopin in 1830s Paris.

Mannequin on the Move - Sequel to "Mannequin," the further comic adventures of the department store dummy that comes to life.

Stone Cold - Surly ex-football star Brian Bosworth tries musclebound movie heroics as an undercover cop.

Truth or Dare: On the Road, Behind the Scenes and in Bed with Madonna - Documentary/concert film of Madonna's "Blond Ambition" tour last year.

What About Bob? - Psychiatrist Richard Dreyfuss' vacation is disrupted by patient Bill Murray.

Backdraft - Serious look at firefighters, with Ron Howard directing Kurt Russell, Scott Glenn, Robert De Niro, Donald Sutherland, Jennifer Jason Leigh.

Drop Dead Fred - Phoebe Cates' imaginary childhood playmate returns in this romantic comedy.

Hudson Hawke - Action-comedy with Bruce Willis as a cat burglar in a plot to rob the Vatican.

Only the Lonely - Maureen O'Hara, back on the screen after 20 years, plays John Candy's mother.

Superstar: The Life and Times of Andy Warhol - Documentary on the New York artist.

Thelma & Louise - Geena Davis & Susan Sarandon star in this comedy-drama about two stifled women who hit the road. Filmed in southern Utah.

Wild Hearts Can't Be Broken - True story of a young stunt rider who is blinded.

Soapdish - Comedy about TV soap opera, with Sally Field, Whoopi Goldberg and Kevin Kline.

Also possible before the end of May: Journey of Hope, the sentimental Swiss film that won the Oscar as best foreign-language film; A Rage in Harlem, a comedy-thriller with Forest Whitaker, Danny Glover, Gregory Hines and Robin Givens.

JUNE

City Slickers - Yuppie Billy Crystal leaves Manhattan to become a cowboy in this comedy. (3)\ Fires Within - Jimmy Smits is in love with a Cuban political prisoner's wife. (7)\ Jungle Fever - Spike Lee's latest is about an interracial romance.(3)

Robot Carnival - Japanese sci-fi animation.(7)

Ay Carmela! - Cabaret performers kidnapped during the Spanish Civil War; a Spanish film. (14)

Robin Hood - Kevin Costner as the bandit of Sherwood Forest, with Mary Elizabeth Mastrantonio as Marian. (14)

Shattered - Amnesiac Tom Berenger is manipulated by his scheming wife in this thriller. (14)

Citizen Kane - The Orson Welles classic is re-issued in a new, touched-up format. (14)

Dutch - John Hughes comedy with trucker Ed O'Neill transporting his girl's snobbish son. (14)

Leningrad Cowboys Go America - A Finnish band travels across America; a Finnish comedy. (14)

The Rocketeer - Disney comic book thriller about an ordinary guy who finds a jet pack. (14)

Billy Bathgate - E.L. Doctorow's novel about '30s New York gangsters, with Dustin Hoffman as Dutch Schultz. (28)

The Naked Gun 2 1/2: The Smell of Fear - Leslie Nielsen stars in this sequel to the "Airplane!" team's off-the-wall cop spoof. (28)

Rosencrantz and Guildenstern Are Dead - Gary Oldman and Richard Dreyfuss star in this adaptation of the stage play. (28)

Also possibly coming before the end of June: Dice Rules, Andrew Dice Clay's concert film, rated NC-17; Dying Young, a drama with Julia Roberts in love with a cancer patient; Clifford, a comedy with Martin Short playing a child; The Taking of Beverly Hills, action with Ken Wahl.

JULY

Problem Child 2 - John Ritter is back in this sequel to last year's surprise comedy hit. (3)

Terminator 2: Judgment Day - Arnold Schwarzenegger's killer cyborg is back, still chasing Linda Hamilton. (3) Daddy Nostalgia - British star Dirk Bogarde's first film in 12 years has him as a wealthy, retired gentleman facing death and reconciling with his family. (5)

Another You - Richard Pryor and Gene Wilder team up again in this mistaken-identity comedy. (12)

Boyz N the Hood - Coming-of-age in the south L.A. ghetto. (12)

Don't Tell Mom the Babysitter's Dead - Christina Applegate (TV's "Married . . . With Children") stars in this dark comedy. (12)

101 Dalmations - Disney's delightful animated classic is reissued.(12)

Point Break - Patrick Swayze and Keanu Reeves star in this caper-thriller. 12)

Poison - Controversial winner of the Sundance Film Festival's Grand Prize. (12)

Regarding Henry - Harrison Ford as a lawyer changed by tragedy; directed by Mike Nichols. (12)

Doc Hollywood - This comedy has Dr. Michael J. Fox's car breaking down in South Carolina. (19)

L'Atalante - Restored 1934 French classic about a young newly married couple. (19)

Mobsters - Young mobsters, to be precise - Christian Slater, Richard Grieco, Patrick Dempsey.(19)

Radio Flyer - Coming-of-age story about two boys involved with myths and magic. (19)

Warshawski - Kathleen Turner is a tough private eye in what may be the first in a series.(19)

Hot Shots - Charlie Sheen stars in this "Airplane!"-style parody of "Top Gun." (26)

Iron and Silk - True story of young American teacher in China changed by the culture.(26)

Return to the Blue Lagoon - Unknowns star in this sequel to the Brooke Shields hit of 11 years ago.(26)

Rockadoodle - New animation/live-action feature from Don Bluth ("All Dogs Go to Heaven"). (26)

Also possibly coming before the end of July: Bill and Ted's Bogus Adventure,literally, in this sequel with the same cast; Curly Sue, a John Hughes comedy with James Belushi; Lame Ducks, the Zucker Brothers ("The Naked Gun") created this Marx Brothers-like farce.

AUGUST

British Animation Invasion - Another collection of animated shorts, these from England. (2)\ Child's Play 3 -- Killer doll Chucky returns.(2)

Harley Davidson and the Marlboro Man - Don Johnson and Mickey Rourke team up.(2)

True Identity - Gangster comedy with British comic Lenny Henry.(2)

Double Impact - More muscle action with Jean Claude Van Damme as twins.(9)

Rover Dangerfield - Animated feature, starring a dog patterned after Rodney Dangerfield. (9)

The Commitments - British musical drama about the rise of a young band.(16)

Other People's Money - Comedy about corporate takeovers with Danny DeVito and Gregory Peck.(16)

The Doctor - Drama with William Hurt as a heart surgeon who finds he has cancer. (23)

Life Stinks - Mel Brooks is a wealthy businessman who bets he can spend a week on the streets with the homeless.(23)

Also possibly coming before the end of August: Barton Fink, a comedy with John Goodman; Bingo! a comedy with Cindy Williams; The Butcher's Wife, psychic drama starring Demi Moore; Car 54, Where Are You? a comedy based on the TV sitcom; Delirious, a comedy about soap operas, with John Candy; RoboCop 3, a sequel without Peter Weller; The Super, a comedy about a slum landlord (Joe Pesci) ordered to live in one of his own tenements; Welcome to Buzzsaw, Matthew Broderick stops in the wrong small town in this comedy.