Directed by Claude Chabrol, who wrote the screenplay based on the novel by Charlotte Armstrong, 2000's Nightcap (known in its native France as Merci pour le Chocolate) revolves around Mika Muller-Polonski (Isabelle Huppert), the first and third wife of Andre Polonski (Jacques Dutronc), a renowned pianist who has made quite a good life for himself with his musical abilities. When they were young they got married rather impulsively but that didn't last long. When they split, he remarried with a woman named Lisbeth (Lydia Andrei) soon after and had a son that they named Guillaume (Rodolphe Pauly). Tragically, Lisbeth died in a car accident after she fell asleep at the wheel on the way home from a visit with none other than Mika.

Almost two decades after their first marriage, with Guillaume now a grown man, Mika and Andre wed that second time. After the lackluster ceremony they go about moving into Mika's massive and stately old mansion. Her own family has owned and operated a very profitable chocolate company for years, she's obviously not in this for the money. One thing that she does insist on, however, is that she prepare and serve her husband and stepson a cup of hot chocolate each night before bedtime. She adheres to this tradition with almost ritualistic strictness. Things get… odd when Jeanne Pollet (Anna Mouglalis), a piano protégé, discovers that when she was born, for a very brief instant at the hospital where the birth took place she was switched with Guillaume. She uses this strange bit of information culled from her mother's archives to introduce herself to Andre in hopes that he'll take her on as a student. He obliges, while Guillaume's introversion becomes more intense. As Jeanne Pollet and Andre become closer in their work together, Mika maintains appearances and insists, as usual, on serving everyone hot chocolate.

The suspense in this picture comes not from knowing what Mika is doing with her hot chocolate but why, to whom and most important of all, when. Of course, all of this ties into Andre's past and not surprisingly at all the introduction of beautiful Jeanne Pollet and all of the secrets that are revealed as the plot progresses and skeletons not so coincidentally fall out of the closet. For the most part this works well, it turns out to be a fairly atypical murder mystery, but on the flip side of that coin is the fact that the ‘whodunnit' aspect is obviously underplayed and therefore things are paced rather meanderingly. Those expecting action and big set pieces as the movie draws to a close may also be a bit taken aback by the fact that this is an exceedingly character driven piece that relies far more on dialogue than on shadowy set pieces or graphic murder scenes.

Chabrol being Chabrol, however, manages to keep this entertaining. He's not solely responsible though, as a good bit of the credit for that goes not so much to the director as to the cast. Isabelle Huppert, who had worked with director before, has an appropriately detached demeanor here. She's pleasant on the surface and at first glance seems nice enough but there's something icy and cold underneath her superficial smiles. This makes her quite effective in the role. Likewise, Jacques Dutronc and Rodolphe Pauly as husband and step-son respectively, also do fine work here. They keep us guessing as to how aware they are of what's going on around them and as the script slowly but surely offers up more details about all involved, their characters do become more interesting. Anna Mouglalis is not only gorgeous but manages to play her part just as well as anyone else in the cast. With important aspects of the plot revolving steadily around her character, obviously that's important and she pulls it off. Add to that a nice score and some excellent cinematography that effectively shows off some beautiful locations, and Nightcap turns out to be a well-made film and a decent watch. If it's not on par with some of the undisputed classics in Chabrol's filmography, so be it, but for the most part it works quite well.

Nightcap arrives on Blu-ray in a 1080p high definition offerings from Cohen framed at 1.66.1 widescreen, which looks like the film's aspect ratio. Colors lean towards greenish-blue in spots which takes away from some of the pop you might hope to find here but otherwise the transfer is quite good, if never completely remarkable. Detail is definitely stronger than you'd get from a standard definition offering but some scenes do look a bit soft and sometimes things look unusually smooth, as if some minor noise reduction has come into play. It doesn't obliterate the image, however, and the picture is quite clean showing no serious print damage or serious compression artifacts. The colors do look a bit off though, as if this darker than it should be.