Forgotten Book - A Little Less than Kind

Charlotte Armstrong's A Little Less than Kind can be read on its own merits as an unusual novel of domestic suspense, concerning the suspicions of a young man, Ladd Cunningham, that his father was murdered by an old friend called David Crown, who has now married Ladd's mother and taken control of the family business. Alternatively, one can pick up the clue in the title and read the story as a Sixties riff on Hamlet with a fair dollop of Freudian psychology thrown in.
On the whole, I prefer the former approach. The set-up is full of potential. Hob Cunningham was dying of cancer, but Ladd's prejudice against David leads him to suspect that David hastened Hob's death. His interpretation of events seems, to him, to be justified by a coded message Hob has left behind. Ladd determines to kill David, and his attempts to cause mayhem become increasingly deranged.
The story offers lead characters who are equivalent to those in Hamlet, but Armstrong is not attempting to rewrite the play, but rather to do something different inspired by the ideas in the play. She's interested in the relations between parents and children, a key theme of the novel, and in the question of taking responsibility. David's new wife Abby, who believes in courtesy and avoiding any hint of an argument, is portrayed as charming but selfish and weak.
There is some good writing in this novel, particularly in the early chapters, and some building of suspense. But then the story begins to drag, and the finale, though not short of action, is rather anti-climactic. It's almost as if Armstrong's interest in Shakespeare and psychology derailed the story I wonder if she began with an idea which she didn't think through fully? It's an intelligent book with pleasing aspects but not a complete success.