I won't rehash the storyline which everyone knows but just a few comments:
Plus points:
-the first film adaptation which sticks to the ending as outlined in the novel
-dialogue is very much as per the novel. If you know the book well, the subtitles are almost superfluous
as you will know what the characters are saying
-the choice of location for filming was inspired. Oddly, the external shots feel more claustrophobic than those inside the house. The crucial scene at the end between Vera and Lombard is powerfully shot with the sea almost a background character on its own.
Minus points:
-At times it can be difficult to distinguish Lombard from Blore. Facially, they are very alike.
-The actress playing Emily Brent is too young...equally, the character playing Anthony Marston is some 10 years too old.
-There's something lacking with the interior shots which fail, at times, to convey the cloying claustrophobia so evident in the book. It may be that there are simply too many daylight scenes.
While I prefer the 2015 BBC adaptation, this 1987 Soviet version is in second place, well ahead of any of the previous adaptations.
However, no film version will ever beat the novel itself and the imagery those words conjure up in the reader's imagination. It's still the only book I can pick up and read from start to finish without a break.