Captain MacKenzie Calhoun has faced incredible odds before, but nothing he has ever experienced could prepare him for the simultaneous threat from two of the most destructive forces he's ever come across. The first is the D'myurj-a mysterious and powerful alien race bent on either the complete domination of humanity or its destruction. The second is even more alarming: Morgan Primus, once a living creature with a soul and a conscience, now an incredibly sophisticated computer simulation taking up residence within the very core of the USS Excalibur...and quickly becoming a growing menace for the Federation....