In His Shadow — Michael Horton

People live with shadows, and shadows have minds of their own. When they act against the light, Val and Ika are called into action to put a stop to them. Shadows can corrupt minds and destroy the bodies of those unwittingly possessed by them, a fate inevitable for those sheltering deep, dark secrets. Ika will have to sacrifice her own heart to protect her soul, but losing Val might be more than she can handle.