Mika Muller marries renowned pianist Andre Polonski in beautiful Lausanne Switzerland after his wife dies. Soon after 18-year-old pianist Jeanne Pollet learns that she and Polonski's son Guillaume were momentarily switched at birth at the hospital where they were born. When Jeanne's curiosity is further piqued by the coincidence that she not Guillaume shares Andre's gift for the piano she pays an unexpected visit to the Polonskis' lovely Lausanne home. There she meets the polite but detached Mika the somewhat aimless Guillaume and the pianist himself. Andre is taken with Jeanne's skill at the piano and offers to instruct her while Mika feigns tolerance. But Mika has other distractions: As head of her family's chocolate business she struggles to keep it on firm economic ground. Also on a more sinister note she tampers with the hot chocolate she often serves to the extent that it dangerously sedates those who drink it. After Mika clumsily spills the drink Jeanne's suspicions are aroused and her boyfriend Axel--a budding scientist--confirms that the hot chocolate is tainted. A tragic auto accident in which Andre's second wife was killed provides further clues. On a subsequent fateful night when Jeanne and Guillaume are driving together Mika is finally revealed to be the stone-cold monster that she is.
Once again Isabelle Huppert here starring as Mika takes on and owns the role of a totally repugnant person. Other examples include the recent The Piano Teacher and The Ceremony this latter also a collaboration of Nightcap's director Claude Chabrol and screenwriter Caroline Eliacheff. Huppert an amazing actress who is a vet of dozens of films has a challenge on her hands with Nightcap mainly because her villainous character is so Swiss bourgeois cold and abstruse. Still absenting the fact that Huppert doesn't spill chocolate very convincingly her performance mesmerizes. As Andre Jacques Dutronc familiar to French film fans convinces as the largely clueless pianist focused solely on his art. Others including Anna Mouglalis as Jeanne and Brigitte Catillon as her mother Louise are fine in their roles. Foreign film buffs will also welcome the participation of vet Swiss actor Michel Robin portraying one of Mika's pesky executives.
Vet French director Chabrol delivers beautiful Lausanne settings elegant music and mostly flawless bourgeois characters in a soapy melodrama that is easier to watch than believe. With scores of films to his credit Chabrol is a master of the kind of cool elegant ironic suspense that informs Nightcap but his problem here is that he doesn't have a terribly credible story. Still he elicits interesting performances from his actors and delivers a cool elegant style that befits the refined upper-class Swiss settings. As for irony Chabrol lays on a multitude of elegant music pieces (both from the classical repertoire and composed by his son Matthieu) that are an ironic counterpoint to the evil bubbling at the film's nasty core.