Meredith wakes up from a dream where she is given a horn cup from the Consort. The horn is a lost relic belonging to Abeloec, one of her guards, and the former god of wine. Abeloec and Merry drink from the horn, and some of his former god powers are restored. The other guards receive tattoos, symbols of their former god-powers that link the guards to Meredith in a mysterious way. Like her Anita Blake series everything revolves around sex and a new power to save the day.
They are magically transported to the heart of the Unseelie sithen, the dead gardens, where sex with Meredith, Abeloec and Mistral causes the gardens to come alive again. Rain begins to fall inside the garden.
Through the sex magic, Galen, Nicca and Aisling disappear into the earth, air and trees, apparently as sacrifices to bring the magic back. Merry discovers that the Sithen responds to her desires, like adjusting how much rain falls in the garden. Merry learns that Abeloec’s cup was once used to make queens and goddesses, and the group speculate as to whether Merry is now immortal.
Meredith asks the sithen to create a door to return to the Unseelie sithen. When they go through it, they find that they have accidentally passed into the Sluagh sithen, and they end up in the dead garden of the Sluagh. Before they can escape, they are confronted by Sholto, King of the Sluagh, and Lord of That Which Passes Between, and his two night hags, Agnes and Segna. Meredith discovers that Sholto’s tentacles have been shaved off by a member of the Seelie who tricked him. The hags believe that Meredith is part of the conspiracy. Segna attacks Meredith, but before she can reach her, Sholto strikes her and throws her into the dead lake, where is she is speared by the enchanted bones of the dead. Segna is mortally wounded, but alive. Sholto and Meredith wade into the lake to euthanize Segna. In a last ditch attempt to kill Meredith, Segna pulls her under the water. Meredith uses her Hand of Blood to finish Segna.
Sholto and Meredith magically appear on the Island of Bones in the middle of the lake. Sholto carries a dagger and a spear of bone, signs of kingship among the sluagh that had been lost. The Goddess appears and gives Sholto the chance to restore magic to the Sluagh. He is given the choice to either bring the magic back with blood by killing Meredith, or by sex. If he chooses death, the black heart of the sluagh will be restored. But if he chooses sex and life, it will change the sluagh sithen to a more Seelie-like place. Sholto chooses sex and life, and together they restore magic to the Sluagh garden. In a blast of power, they are returned back to the Sluagh garden which is now filled with herbs, plants and flowers.
Drunk with his new power, Sholto calls the Wild Hunt to chase the sidhe. Meredith and her guards flee. Meredith conjures a protective covering of four-leaf clover and discovers a “thin place” that allow them to escape the Sluagh sithen. Now more sidhe than ever, Sholto is attacked by the very Wild Hunt that he called up, and he is forced to flee as well.
Now in the real world, Meredith calls on a group of Red Hats (cousins of the goblins), led by Jonty, to fight the Wild Hunt with them. The Wild Hunt is defeated and through the remaining magic, faerie animals including dogs appear.
After the battle, they are rejoined by Galen, Aisling and Nicca who, having disappeared from the garden, reappeared in the Hall of Mortality. Galen’s wild magic causes flowers and water to appear in the Hall, and he accidentally causes all prisoners to be freed, including Cel, the Queen’s son, who wants Meredith dead. A furious Andais confronts Meredith and tells her that she must take her guards and go back to Los Angeles tonight, because she has ruined her sithen and Andais cannot keep her safe from Cel.