Catharina van Bohemen, reviewing for the New Zealand Review of Books, praised Grimshaw's "sense of humour, her delight in words, her ability to create atmosphere through evocative descriptions of the weather and the landscape, and the novel's strong conclusion", and said these strengths outweighed "occasional quibbles that there are too many characters or that nearly all the men's eyes are bloodshot".
One reviewer commented that the book "could have degenerated into a mess", but Grimshaw's "deft hand with characterisation, irony and wit and an eye for deviant behaviour makes gripping reading".
[16] The judges' comments said: "By turns touching, funny, dark, and redemptive, this is a book for reading through then re-reading in a different order, for following clues, for setting aside and thinking about, and for getting lost in.
[18] Singularity was shortlisted for the Frank O'Connor International Short Story Award and for the South East Asia and Pacific section of the Commonwealth Writers Prize.
[19][8] Her subsequent novels, The Night Book (2010),[20] Soon (2012),[21] and Starlight Peninsula (2015),[22] further explored the cast of New Zealand characters and settings from her collections Opportunity and Singularity, including in particular David Hallwright, a National Party Prime Minister, and his friend Dr Simon Lampton, an obstetrician.
"[26] Grimshaw has said that in writing Opportunity and its successors she wanted "to explore our many and varied New Zealand voices, accurately, without sentimentality", and that she was inspired by La Comédie humaine, Balzac’s linked novels and stories.
"[31] Charlotte Graham-McLay in The Spinoff described it as "at once domestic drama, psychological thriller — underscored with a buzzing note of menace about global terrorism and the surveillance state — and a sort of sensual coming-of-age tale".
[32] In The Mirror Book (2021), a memoir, Grimshaw writes about her childhood and family relationships growing up in the Stead household.
[33] She has described the memoir as acting as a companion to her novel Mazarine, and had developed them together as part of a planned project called The Mirror Books: "They’re an examination of that material from two different angles.
"[35] Emma Espiner described Grimshaw as "a woman with the courage to test the edges of what she's been told is true, to see if it holds", and praised the book for its personal revelations and its connections to universal experiences and cultural narratives.
[36] Rachael King, reviewing the book for the Academy of New Zealand Literature, noted the relationship of The Mirror Book to Mazarine and the short story "The Black Monk": "the three pieces of writing — novel, short story and now memoir — are a fascinating project, an examination of the very notion of autobiography: of fact, of fiction, and of truth".
[41] In 2006, Grimshaw won the Bank of New Zealand Katherine Mansfield Award for her short story "Plane Sailing".