This book is the story of Penelope, wife of Odysseus, not-so-stunning cousin of Helen. Atwood relies primarily on The Odyssey but also uses modern research on these myths to create the story from Penelope's point of view. Penelope is known as "the faithful wife", because she did not stray once during the 20 years her hubby was off wandering, first to fight the Trojan wars, then later to fight his way home again, encountering one challenge after another (or so he says). During the second ten years, Penelope is besieged by suitors, men not much older than her son, Telemachus, who come for her hand in marriage. They assume Odysseus is never coming home and they clearly want her riches. Thus they camp on her doorstep and eat her practically out of house and castle.
During this time she knows that she cannot alone get rid of them and that if she tells them to leave then at least one will choose to take her by force. So she tries various tricks. One is to weave a shroud for her father-in-law. She says that when she has finished the shroud she will choose her new mate. She weaves during the day, and with the help of twelve young maids she secretly unravels at night, so the shroud will never be finished. Thus the term "Penelope's web", referring to a thing that is never finished.
The real focus of this version of the myth is the death of the twelve maidens. When Odysseus returns, he and Telemachus, along with two servants, kill all the suitors - over a hundred of them - and then string up the twelve maidens because they had had sex with the suitors "without permission". Typically in those times, the master of the house gave permission to guests to use his servants, to rape them, but because there was no man of the house the maidens were taken without permission. And so they were found complicit with the suitors.
There is, of course, more of a backstory, and Atwood succeeds, I believe, in explaining these deaths better than the Odyssey does.
The book is short, readable, often funny. I zipped through it. It is part of a series of myths retold by modern authors. How inspired to ask Atwood to do this.