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TomKat Wedding | Robert Downey Jr. | Demi Moore

TomKat Wedding Guests: Plane Talk

The Tom Cruise-Katie Holmes wedding will be a little different than most. Expect a bride’s side, a groom’s side and a Scientologist’s side.

That’s because Cruise is planning to fly over all the big name celebrity Scientologists to his European (Paris or Rome — take your pick) wedding in a plane he’s chartered especially for them. Sources tell me that Leah Remini, Kirstie Alley, Jenna Elfman, John Travolta, Kelly Preston, and Priscilla and Lisa Presley are all on the manifest. Remini is among the few people in the world to have actually seen Cruise and Holmes’s baby daughter, Suri, in person and commented on her.

Indeed, only members of Cruise’s Scientology circle were offered to the press as those who’d seen Suri before her pictures appeared in Vanity Fair.

The plane is being booked by Cruise’s personal staff, and should leave Los Angeles several days before the Nov. 18 wedding in Italy (or France).

The guest list, insiders say, also includes all the top dogs at Scientology, including leader David Miscavige, Helio and Earthlink founder Sky Dayton, as well as Cruise’s best friend, Tom Davis, son of actress Anne Archer. Davis was Cruise’s constant companion in between Cruise’s Penelope Cruz and Katie Holmes chapters. He turned up unexpectedly at the premiere of "Collateral," where guests were surprised by his resemblance to the movie star.

The Presleys are likely guests at the wedding for another reason. Insiders are quick to point out that in 2000, Priscilla — an active Scientologist — was appointed to the board of directors at MGM, the company that owns United Artists and the place where Cruise has now found refuge after his very public embarrassment with Paramount.

Sharp-eyed observers will also be looking for members of the Feshbach clan, the controversial, Palo Alto-based investors who have donated millions to Scientology and run a couple of their centers. Daughter Jessica was Katie Holmes’ assigned watcher when the "Dawson’s Creek" actress first became involved with Cruise. With all of Holmes’ close pals gone since that period — including former hometown best friend Meghann Birie and actress Rebecca Gayheart, among others — it should be interesting to see if Feshbach is the bride’s matron of honor.

Robert Downey: No 'Juice' for Iron Man Bulk-Up

It’s been Robert Downey Jr. week here in New York, since the Oscar nominated actor has not one but two hot films to promote.

And it isn’t easy, since Downey — who’s had his public problems with substance abuse — is now undertaking a serious health regimen. The reason: He has signed to play superhero Iron Man for director Jon Favreau and Paramount. The 41-year-old actor told me he won’t be "hitting the juice," i.e. taking steroids or any other special energy drinks to pump himself up for the part.

"I have a great trainer and we’re just doing it the old-fashioned way," he said.

Downey could have used at least a PowerBar the last couple of days as he did yeoman service for his two current movies. On Sunday night he made the rounds for Steven Shainberg’s Diane Arbus film, "Fur," in which he plays most of the movie covered in a costume that closely resembles the Cowardly Lion. Downey’s character is one of the many odd types with whom the legendary photographer trafficked. Nicole Kidman, of course, is Arbus, in this weird and courageous art-house film that will have audiences talking when it opens on Friday.

But it was last night’s screening of "A Guide to Recognizing Your Saints" that really got the fur flying, since Downey was trying to get downtown to a birthday dinner for new-ish wife, Susan. Nevertheless, the couple was featured at Florence Gould Hall, where producer Trudie Styler and husband, Sting, welcomed a range of actors and industry types that included Swoosie Kurtz, playwright Israel Horovitz, "Shine" director Scott Hicks, singer-songwriter Suzanne Vega, Revlon chairman Ronald Perelman, horn player Chris Botti, former "Law and Order" actress Elizabeth Rohm, and Dan Aykroyd and wife, Donna Dixon, still sizzling after all these years.

Before the film started, Downey, who is also great in "Saints," graciously told the audience to look out for the many fine performances in the movie by other actors.

Later, the whole gang was invited back to Chez Sting/Styler on Central Park West, where First Look Studios chairman Henry Winterstern re-dedicated himself to a "Guides" awards campaign, particularly for supporting actor Chazz Palminteri, who is so exceptional playing Downey’s dad in the film.

Demi Moore: She Gotta Go Now

Get ready, because Gwyneth Paltrow’s singing gig in "Infamous" — a movie you should try and see, by the way — is about to be topped.

Demi Moore is making her own vocalist debut in "Bobby," Emilio Estevez’s dazzling ensemble film about the people at the Ambassador Hotel on the day Senator Robert F. Kennedy was assassinated in 1968.

In the film, Moore plays a boozing nightclub singer named Virginia Fallon. For verisimilitude, at one point Moore must get up and sing before an audience. She does, and her version of "Louie Louie" — arranged to resemble Dusty Springfield’s "Wishin’ and Hopin’" hit from that era — is genius.

Demi’s late mother was also an alcoholic, and Moore’s performance in the film is so poignant and real that Estevez recently told me, "She’s playing her mother." It’s the best work Moore has ever done.

Now, it seems, the full performance will be on the "Bobby" soundtrack coming from Island/Def Jam Records. It’s so unusual that "Louie Louie" could wind up being a surprise hit on adult contemporary stations. Moore’s trademark gravelly voice is perfectly suited to the song, counter-pointed to the Las Vegas-y orchestration. Who knows? Stranger things have happened!