Anna and Andrei marry and live in the city where she is a nursery-school teacher and he is a paediatrician at the local hospital.

The child is the son of Volkov, a Commissar of State Security, and while Andrei knows the dangers if things go wrong, he is determined to give the boy the best possible care.

Volkov accuses Andrei of butchering Gorya for no reason and of being part of a conspiracy by doctors to murder Soviet leaders.

[5] In a review in BookBrowse, Sarah Sacha Dollacker called The Betrayal "[a] powerful novel" with "expertly drawn" characters, convincing dialogue and believable conflicts.

[6] British poet Carol Rumens wrote in The Independent that Dunmore's dialogue is "powerful" and "subtle", and connects the book's two adversaries, Volkov and Andrei "in a way that shocks, surprises and moves us".

[7] Reviewing The Betrayal in The Guardian, Susanna Rustin described the novel as "an absorbing and thoughtful tale of good people in hard times".

Rustin remarked that while The Betrayal "falls far short" of other historical works, like Pat Barker's Regeneration trilogy, Dunmore's "intelligence and gift for narrative" makes her books something to look forward to.

[9] She said the book's "impalpable apprehension", Andrei's conflict between his doctor's instinct to heal and his "panic-stricken desire" to protect his family, "is chillingly described".