As Hercule Poirot points out in the latest Agatha Christie film, "Everywhere there is evil under the sun." First there was "Murder on the Orient Express," with an exacting Albert Finney as a dapper Poirot. Then came "Death on the Nile," with Peter Ustinov playing his fat and precious version of the Belgian detective.

In this new Christie mystery -- the fourth produced by John Brabourne and Richard Goodwin, who also made "The Mirror Crack'd" -- Ustinov takes his second stab at the Poirot character, this time coming across as a coltish Maurice Chevalier done up in Belgian drag. The results make for mild amusement: a diversion for a wet afternoon.

Overall, that's the way of "Evil Under the Sun" and its predecessors. They're like cocktail parties where glamorous women in outrageous clothes make catty comments while paunchy men nod off over Singapore slings and sidecars. It makes you want to go for another drink or take a smoke in the foyer. In truth, when the mysterians are not in their rooms changing clothes or out tanning, they are having cocktails to Cole Porter.

This time around, the Christie characters have gathered at a luxurious hotel on the Adriatic -- really Majorca during a pollution alert -- where a shrewish Broadway actress named Arlena, played by Diana Rigg, is caught in flagrante delicto with a nice young Latin teacher, played by Nicholas Clay, who smokes a pipe and wears a swimsuit that's a size too small.

Those also caught up in ther affair are his plain and pathetic wife (Jane Birkin), the hotel proprietor (Maggie Smith), a pair of Broadway angels (Sylvia Miles and James Mason), Arlena's husband and step-daughter (Denis Quilley and Emily Hone), a swishy biographer (Roddy McDowall again) and Arlena's old flame (Colin Blakely).

Naturally, one of the well-to-do is done in. And certainly, the motives are as plentiful as the cast-iron alibis. But none of it is a match for the little gray cells of Monsieur Poirot. That's elementary.

EVIL UNDER THE SUN -- At 11 area theaters.