Fiction Chronicle.

THE BETRAYAL By Helen Dunmore. Black Cat. Paper, $14.95. Dunmore gamely returns to Soviet Russia with her follow-up to ''The Siege,'' which captured the frenzy of Leningrad ravaged by German forces in 1941. Eleven years later, the fear and distrust that poisoned relations between war-torn residents has only been amplified. Among the survivors are the members of a family pressed back into service from the earlier novel: a nursery teacher named Anna; her younger brother, Kolya; and her husband, Andrei, a pediatrician who agrees to treat the cancer-ridden son of a high-ranking secret police officer. Not a good idea. Dunmore has also written children's books and poetry, a resume that reveals itself in the economic architecture of her storytelling, which at its most effective can make manifest the bleakness of a totalitarian landscape and at its least seems to read like a starchy translation of Pushkin. But she's good at planting unobtrusive walk-on characters who step upsettingly to the forefront as Andrei's predicament careers toward its preordained crash. ''The Betrayal'' pulls readers along with the queasy allure of long-anticipated bad news. [ABSTRACT FROM PUBLISHER]