The Water Dancer is set in Virginia, during the time of slavery. Its universe is close to that of the historical antebellum American South, but has added surreal elements. In The Water Dancer, the enslaved are known as the Tasked, and the slaveowners are known as the Quality. The protagonist, Hiram, is an enslaved African-American man who was born and raised on a tobacco plantation and estate called Lockless. Hiram’s mother, Rose, was enslaved, while his father, Howell Walker, is the white master of Lockless. Howell’s white son, Maynard, is Hiram’s brother, master, and the heir of Lockless. When Hiram is nineteen, Maynard dies in an accident in the river Goose.
Hiram has a photographic memory but he can’t remember his mother, nor can he recall how Howell Walker separated them when Hiram was just nine years old. Hiram also possesses a special power called Conduction, which allows him to transport himself, and eventually other people, from one place to another. Hiram tries to run away with a woman he loves, Sophia, but the slave hunters catch them and separate them. Eventually the Underground, a network of resistance to slavery, rescues and recruits Hiram. He makes his way north to the free city of Philadelphia, where he works with the Underground while struggling to adapt. Eventually, Hiram meets Harriet (based on the historical figure Harriet Tubman), known as a Moses, a powerful Underground agent who helps him to understand that Conduction works through the power of memory.
Hiram returns to Virginia to help the Underground there and to rescue his loved ones: Sophia and his childhood caretaker, Thena. He works as his father’s servant so as to provide intelligence to the Underground. He learns to better control Conduction and uses this power to send Thena north to Philadelphia. Meanwhile, Hiram and Sophia remain at Lockless, forming a romantic relationship and caring for Sophia’s baby, Caroline. Eventually, Howell Walker dies and the Virginia Underground takes over his estate through the clever scheming of Corrine Quinn, a wealthy white woman who is a leader in the resistance to slavery. Hiram manages the estate and station of the Underground.