The premise of the book is an autobiographical confession of the protagonist, Iris Chase. She writes upon her deathbed and intends to turn the novel over to her only surviving relation, her granddaughter. Iris and her sister Laura grew up in Ontario. Despite being raised by a single father, they were happy children. Iris recalls some important memories from her childhood and adolescence, anchored with historical events of the time. As adults, she marries a harsh older man named Richard Griffen. They have a daughter, and remain married for many years.
After recording her teenage years, Iris includes a novel within her novel. It's supposed to be written by Alex Thomas, a science fiction author with a radical bent. Actually Iris is still the author, but within the novel she attributes this pulp fiction inset to her sister, Laura. Alex has a tumultuous love affair with a woman who also writes a story which is included in Iris' memoir. This science fiction work, The Blind Assassin, is a thrilling account of another love affair. Iris leads her readers to believe that her novel-within-a-novel is about her sister's love life with a man named Alex. After the novel-within-a-novel's end, Iris comes back to her real life account.
Laura learns that Alex has died in the war. Immediately she kills herself. Shortly after, Iris finds her sister's journal and learns that she had been blackmailed and raped by her own husband -- Richard -- for years. Iris then confesses that the novel "written by" Alex is actually about herself and her affair with Alex. She learns from Laura's diary that Richard got her sister pregnant and forced her to have an abortion. Needless to say, she becomes greatly afraid and horrified at his actions. She takes her daughter, Aimee, with her and leaves her husband.
Alone and abandoned by all of her family, Iris struggles to parent as a single mother. She frequently contacts Richard, continually upsetting her daughter and damaging their relationship. When questioned, Iris convinces Richard that Laura was actually the one who had an affair with Alex. The news is too much for the already unstable Richard, and he commits suicide. Iris winds down her narrative, writing up to the moment of her death. She bequeaths her unpublished autobiography to her granddaughter, hoping that she will accept the responsibility of its secrets.
