"Kirkus Reviews" called the writing "Beautifully detailed." Kirkus Reviews also complimented "Tamar" by commenting "Stark in its realistic portrayal of the horror and random violence of war [and its d]escriptions of the daily brutality of merely surviving." Literary critics remarked on Mal Peet's exceptional storytelling. Jan Mark wrote: "This sombre and distinguished book is as fine a piece of storytelling as you are likely to read this year", and "The Bookseller" review said: "Beautifully written and absolutely gripping, this is exceptional storytelling." Kirkus Reviews complimented the book as "beautifully detailed writing." Booklist Publications agreed, saying "complex and surprising, this [novel] grows richer with each reading." Roger Sutton of "The Horn Book Magazine" commented that "readers might think that they've wandered into Ken Follett territory for this novel." He also wrote and explained that "the writing is dramatic, and the covert Resistance activities are suspenseful and rich with the details of undercover warfare." However, he complains "["Tamar"] is a satisfying genre fiction, it is only when the book introduces the YA slant 100 pages in that things become a bit awkward." School Library Journal disagrees though, and praised the novel as "intense and riveting" and called "Tamar" an "extraordinary, gripping novel." The emotional side of the novel has been acknowledged by Booklist, who commented that "Peet's sturdy, emotionally resonant characterization and damatic background will pull readers forward," and "despite foreshadowing the outcome is still a stunner." "Tamar" has also been noted by the "North Devon Journal", who said "the story, a mixture of fact and fiction, will make its way into your mental nooks and crannies like ivy spreading across a wall," and that "this novel, like the ivy, will cling to your emotions." Kliatt mentioned that "Tamar" "read like a thriller, with the action of wartime (Winter, 1945)," and that it was "demanding, carefully written story, with dreadful details of betrayal and violence." It was considered to transcend the category of young-adult fiction: "This is an outstanding novel. Outstanding in every regard. It establishes Peet as a novelist of immense gift and versatility, for no two novels could be more different than "Keeper" and "Tamar" and yet be so equally brilliant. ... Tamar is a novel worthy of standing with the very best of contemporary British fiction."