Defiant is the third book in the Kris Longknife Series. It recounts Kris Longknife's experiences as a lieutenant in the United Sentients Navy, centering on a hostage situation of Hikila. She returns to Wardhaven and battles a sneak attack by ships of the Greenfield Confederacy. Kris's attempt to develop doctrine for the use of fast patrol boats is interrupted when the boats are called into service by the Greenfield invasion. Many of the veterans who rally to Kris's side fought in the Iteeche War.
The story takes place in he twenty-fourth century; humanity first left Earth about three hundred years ago.