Ruth Rendell, a consummate artist who commands style, plot and character, has sent us another of her compelling psychological suspense stories. Her latest subjects, daring as always, are child stealing and child abuse.

Benet Archdale, wealthy young author of a best-selling romance novel about India, adores her 2-year-old child, James. Three days after she moves into a gorgeous house in tony Hampstead Heath in London, her madwoman mother Mopsa comes to visit. Things get both curiouser and madder. James develops a cough, then croup; hospitalization follows, and then, as one can easily guess, death. The distraught Benet is also trying to keep her mother from going insane. She can't.

While Benet is at home in a state of collapse after the sad death of James, Mopsa pops out and steals another boy off a wall in a rundown North London suburb where Benet herself used to live. Mopsa returns to Benet's house with Jason and tells Benet she is baby-sitting the boy. Benet, suffering a loss of Shakespearean dimensions (underscored by Rendell's quotations from "Hamlet," "King Lear" and "King John"), finally realizes that Mopsa couldn't possibly be baby-sitting a child for so long. Mopsa then tells Benet that she stole the boy for her. Benet is now faced with a personal dilemma: if she reveals her mother's crime, her mother will be permanently hospitalized for her mental troubles, which have already put her inside for many years in the past.

The secondary plot focuses on the other mother, a feckless woman named Carol Stratford. A petty thief, a user of men, a child abuser, Carol, at 28, has only her sexuality and love for clothing to recommend her. Any maternal feelings are swallowed up in her monumental self-pity and narcissism. She lives with a younger man, a gentle, saint-like carpenter named Barry Mahon, age 20, who has tried to get her to be motherly to her children.

Benet decides to keep Jason, when, while bathing him, she sees cigarette burns and belt buckle scars on his back. By making her mistakenly assume that Barry is the abuser, Rendell scores some very nice, deeply felt points about stereotyping and assumptions about people.

Rendell is always one to complicate the plot and so a third major party drops in: Terence Wand, a frail and foolish fellow who lives off wealthy women. Like some of the others, he eventually earns an appropriate punishment.

Why do people read Rendell? It is not only because she can make such implausible-sounding plots delightful to read. It is not only because her prose style is pleasurable. Most important is her depth of understanding of individual human psyches. She is a superb creator of realistic people -- the reader knows Carol and Benet and Barry and Terry within a few sentences of their appearances in the novel. As usual, Rendell is best at depicting the outrageous in human behavior, for she makes it credible. The most poignant part of this novel is the beginning section, which concludes with the death of James. Benet's deeply felt grief would move a stone to tears. But the subtler grief of Benet's mad mother, who never could be a "proper" mother because of her mental illness, also stirs the reader. And Rendell demands compassion for Carol as well, unthinking, reacting, grieving Carol, whose husband died in a hideous truck crash.

Rendell has it in her to stop fooling with mysteries and sleuth stories. She is a storyteller of a high order. Perhaps this novel signals her turn into writing serious fiction. In any case, she's a good read. Characters, lines, observations stick in the mind.