LITTLE CO-STAR, WARNERS WONDERS WHERE YOU A

Warner Bros.’ “Vision Quest” stars Matthew Modine as a high-school wrestler on a spiritual search.

The studio is now on its own quest: for the film’s co-star.

Linda Fiorentino, a South Philadelphia native who makes a splashy debut in the teen drama, skipped out of Warners’ grasp Thursday in Miami on the first day of a national publicity tour. The studio has been looking ever since for the actress, who is described as flighty--in more ways than one.

“Officially, we don’t know where she is,” said a Warner Bros. spokesman. “Unofficially, she’s somewhere in New York.”

Fiorentino, who has been living in London, arrived in Miami Beach last Wednesday. She got her first look at “Vision Quest” at a local screening that evening. When a Warners field publicist arrived at the Fontainebleau Hotel Thursday morning to shepherd Fiorentino to her first interviews, the actress had checked out, covering her tracks with a Do Not Disturb sign.

“This sounds almost too good to be true, but when we finally got inside (her room) the only thing left was a pair of shoes,” said Miami-based Warners representative David Copeland. “Blue, high-top leather shoes. That’s all I’ve ever seen of Linda Fiorentino.”

The 23-year-old actress plays an itinerant art student in “Vision Quest.” She disappeared on Warners once before, convinced that her screen test had been a flop. After “Vision Quest” (which was in the editing room for more than a year while the original score was replaced with a heavily hyped pop sound track), she starred in Universal Pictures’ “Gotcha,” a late spring release, and in “After Hours” for Martin Scorsese, who reportedly called her “the Bacall of the ‘80s.”

Fiorentino’s current flight has meant no end of trouble for the film’s publicists at Warners and Solters/Roskin/Friedman, all of whom insist it’s no publicity stunt. Interviews and promotional appearances in Atlanta, New York, Boston and Philadelphia have been canceled. A scheduled trip to Los Angeles before the film’s Feb. 15 also is in jeopardy.

Warners claims that it is “in discussion” for Fiorentino’s return. But her agent, Todd Smith of Creative Artists, bridles at the mention of the episode.

“There was no disappearance,” he snapped. Smith would not elaborate, except to say that Fiorentino was staying with family members in a location that he would not disclose.

Replied the Warner Bros spokesman: “She’s disappeared as far as we’re concerned. He proba bly calls it Client Walking Out.”

MONEY MATTERS: Silver Screen Partners, which raised $83 million from 13,000 investors for Home Box Office’s initial slate of theatrical releases, is expected to jump to Walt Disney Productions for its second limited partnership offering.

The new offering would pump about $100 million into Disney’s ambitious new mainstream film plans. Initial details of the plan may be disclosed at the company’s annual stockholders’ meeting in Anaheim today. Disney Chairman Michael Eisner would not discuss the arrangement but did not deny it.

The Silver Screen-HBO alliance has produced “Flashpoint,” a flop last September, and “Heaven Help Us,” a comedy opening Friday. The lineup for the rest of the year includes “Sweet Dreams,” starring Jessica Lange and Ed Harris; “Volunteers,” with Tom Hanks and John Candy as Peace Corp members, and “Head Office,” a corporate comedy starring Judge Reinhold.

HBO Pictures is said to be already seeking a new financial partner for future theatrical movies. The company’s health is of special concern to Tri-Star Pictures, which distributes HBO’s films. The HBO slate is an important peg in Tri-Star’s release schedule at a time when the studio’s own production division has been floundering.

OSCAR BEAT: One definite loser when the Oscar nominees are unveiled today will be Ennio Morricone, composer of the score for “Once Upon a Time in America.”

Morricone’s much-praised music is ineligible because it was never formally submitted for Oscar consideration. Although composers are responsible for submitting their own work, someone like Morricone, who lives in Italy and speaks no English, is customarily reminded and aided by the appropriate studio.

“Once Upon a Time” was produced by the now-defunct Ladd Co and distributed by Warner Bros. Alan Ladd Jr. laments the “oversight” and says that the matter was left in Warners’ hands. A Warners spokesman says that it fell through the cracks while the Ladd Co. was disbanding. The score would have been a top contender alongside those from “A Passage to India” and “The Killing Fields.”

HOLLYWOOD HARDBALL: 20th Century Fox has filed a $25-million lawsuit against Kathleen Turner over a stalemate in negotiations for the actress to star in “Jewel of the Nile,” the sequel to “Romancing the Stone.”

The L.A. Superior Court suit seeks to block Turner from starring in Universal Pictures’ “The Money Pit,” a Steven Spielberg production slated to film at the same time as “Jewel.” Fox claims that the actress has threatened to breach a contractual obligation to appear in “Jewel” unless she is paid “vastly increased sums” for the return role.

Turner’s lawyer, Larry Stein, said Tuesday that Turner has already lost the “Money Pit” role because Fox refused to consider any accommodations in the schedule for “Jewel.” He added that Turner’s differences with Fox include “creative problems” with the sequel as well as salary considerations. Turner has yet to decide on her next move in the matter, he said.

BOX OFFICE: “Beverly Hills Cop” drew another $7.1 million at theaters last weekend, followed by three films in more limited release: “The Killing Fields” ($3 million), “A Passage to India” ($2.5 million) and “The Falcon and the Snowman” ($1.8 million). MGM/UA’s “Heavenly Bodies” grossed a disastrous $1.1 million in saturation release at 1,504 theaters.