To secure their position in the very heart of the Federation, the Cardassians begin constructing space station Sentok Nor in orbit of Betazed. The station is to serve as both the seat of the Dominion occupation and the site of horrific experiments by Cardassia's foremost exobiologist, the infamous Dr. Crell Moset.
With Starfleet's forces spread too thinky in the ongoing struggle to retake Betazed outright, the U.S.S. Enterprise along with some old and new friends, is deployed to carry out a dangerous and desperate plan. But no matter what the outcome, the consequences could alter Betazed irrevocably, forcing Deanna Troi to choose between her world's survival and its very soul.