We never steal children. We only swap them. An eye for an eye, a child for a child.
Aiden must retrieve the Sword Master from demon territory.
The mission doesn't go entirely to plan, and Aiden falls dangerously in love with the Swordsmaster, Keera. She's pretty as a fae, and a strong, graceful fighter.
With every movement she makes, he falls harder. Keera and Aiden both ignore the warnings, marry, and have two beautiful daughters.
Meanwhile, Keera's swords, forged with cold iron, and adorned with silver and gold, have angered the fae—and most especially King Hades and Persephone who rule FaerLand.
Determined to pay the humans back, Queen Persephone orders two fae underlings, Lettie and Zadie to switch their changelings for Keera and Aiden's children.
Lettie's heart breaks as Zadie tears her beloved changeling, Nada, from her hands and replaces her with a snotty human child. Now, the one person she loved in all the world is gone, she will do anything to bring Nada back...
...including killing Keera and Aiden to end the fairy bargain.