I won't say it's a bad film, but I have to believe the liberties taken with the adaptation of the story go well beyond the nudity and modern setting. (I will say that the house with the remote-controlled indoor swimming pool in the living room was a bit over the top.)
I will confess that I did not guess the direction the plot would take, but what was so disappointing was the profusion of loose ends and entirely pointless characters. Agatha didn't usually write them that way - everyone ended up with a role in the outcome of the story. Here we are presented with in-laws, neighbors, family friends, and a mysterious old woman --- all of whom have nothing at all to do with the resolution of the story. Most of them could have been omitted entirely and the story would have been essentially unchanged.
My DVD even featured an editing error: about 10 seconds of the film repeat precisely (when the girl's parents are observed getting back into their car to leave.)
There is also a broken window that is never explained, a ghostly appearance that is never accounted for or revisited, a car is observed to take an unusually long to get somewhere - but we are never given the significance. An architect seems to know things the audience does not -- yet no explanation is offered of how he knows them.
Like Agatha's best writing, characters and clues and complications pile up... but then they are inexplicably thrown away in favor of an unexpected, yet rather anticlimactic resolution.
