The Iron Empires comprise eight nations of peoples scattered across the Milky Way galaxy, being representative of the remains of a decaying human civilization which was once immeasurably vast.

Frustrated with life in the company of her much older husband and bored by dalliances with a string of younger lovers, Sheva assumes command of local forces when the Ganasch, the deformed ape-like minions of the Vaylen, first infiltrate and then invade her planet.

As the narrative unfolds, Sheva is courted by the visiting Philippe of Artois, Count of Karishun, her former mentor and commander and also initiates a new romance with Hardi Degas, a farm-boy turned soldier.

She must lead the resistance of her vastly outnumbered Taramai forces against the incursions of the Vaylen in a series of conflicts ranging up and down the deep forested valleys of her planet.

Indeed, the Vaylen share an acknowledged parasitic relationship with their hosts and as the series progresses treachery rises to the surface of the human defence initiative: Karishun: Look at them down there, Rhiannon.