The success of the movie version of Agatha Christie's "Murder on the Orient Express" encouraged the producers, John Brabourne and Richard Godwin, to mount the expensive, starstudded production of "Death on the Nile" which opens today at four area theaters. Fortune has not smiled on them twice in a row.

Laboriously adapted by Anthony Shaffer and ponderously directed by John Guillermin, "Death on the Nile" fails to rejuvenate Dame Agatha's vintage whodunit, in which Hercule Poirot now played by Peter Ustinov, is obliged to solve a murder among the passengers on a steamer traveling between Aswan and Abu Simbel.

To be fair, the filmmakers seem to have run up against Mrs. Christie in one of her more hectic and arbitrary flights of deception. Still, the alterations made in her leisurely, excessively trickly plot tend to create more problems than they solve.

Guillermin, who appears to have come from Dino De Laurentiis' "King Kong" with a fixation on monuments and head wounds, and Shaffer never establish a confident storytelling rhythm. Although Shaffer has combined and eliminated certain characters, the exposition seems more cumbersome on the screen than it did in the novel, which can accommodate a pokier development.

"Murder on the Orient Express" was a more compact and urgent mystery story. Circumstances obliged Poirot, played by Albert Finney, to rely solely on his wits and reach a conclusion in a limited period of time. "Death on the Nile" beats around the bush before getting down to the initial act of murder.

Neither the event nor the victim comes as a surprise. A haughty heiress named Linnet Ridgeway - (Lois Chiles) has alienated her best friend, Jacqueline de Bellefort, by seducing her intended, Simon Doyle. Jacqueline stalks Linnet and Simon while they honeymoon in Egypt, deliberately popping up in unexpected places (like the top of a pyramid, to cite the most outrageous instance) to disrupt their happiness. She also threatens violence with what turns out to be the murder weapon. Although Jacqueline remains the prime suspect, the other passengers are endowed with a variety of secrets and connections to the doomed Mrs. Doyle that might give them motives for murder.

Christie got a little frantic straining to divert suspicion from the murderous party or parties, and the material is compromised more seriously by the frequency with which Poirot acquires vital information by eavesdropping. It's disappointing to see Poirot's dedective powers play second fiddle to accidental nosiness.

One of the worst ideas in "Murder on the Orient Express" was the repeated reenactment of the murder scene. "Death on the Nile" compounds this vulgarity by visualizing almost every speculation Poirot entertains about his fellow passengers. The redundancy of it all becomes ridiculous.

Poirot's reconstruction of the murders gets so deliriously Poirot's reconstruction of the murders gets so deliriously complicated that the guilty party or parties begin to suggest a French bedroom farce highballing it toward the dennouement. It's certainly an improvement in energy level for "Death on the Nile," but it comes far too late to take up the accumulated expository slack.

Poirot's case seems even shakier on the screen, perhaps because Shaffer and Guillermin insist on having the detective assemble all the suspects in order to broadcast his solution, a stock situation Mrs. Christie wisely avoided on this occasion.

Although a perfectly suitable and capable choice as Poirot, Peter Ustinov lacks the forcefulness and inventive humor that Finney brought to his brilliant impersonation. Finney's performance was cunning and incisive enough to hold "Murder on the Orient Express" togehter when it threatened to grow tedious. Ustinov is always an amiable presence, but never a commanding one.

There are several skillful performers on the periphery, notably Bette Davis and Maggie Smith as a snooty dowager and her sardonic companion, Angela Lansbury (who appears to be metamorphosing, quite deftly, into Margaret Rutherford) as a sozzled writer of lurid romances, and Indian comedian I.S. Johar, a sweell find as the ship's baffled, solicitous manager. As the principals in a romantic subplot, Olivia Hussey and Jon Finch look sensational together and generate vibrations reminiscent of Joan Fontaine and Laurence Olivier in "Rebecca."

The casting of the majestically amateurish Chiles causes needless expository trouble. One of the problems is that Chiles affects a society-girl hauteur that it actively dislikable. The Linnet of the novel was a decent sort, albeit fifthy rich. It seemed monstrous to murder her. The movie Linnet seems to be asking for it.

Mia Farrow, Daisy in "Gatsby and Jacqueline in "Death on the Nile," seems to be making a career out of teaming with Lois Chiles. Although Farrow's scarecrow pallor grows more extreme, her performance in the tricky, ambigous role of Jacqueline has some passion and mystery. It looks especially strong after last week's "Avalanche." By that standard, she easily qualifies as comeback player of the week in "Death on the Nile."