Coming off the disappointing resolution of Clues, TNG bounces back with another mystery that has a much more satisfying conclusion. But I'll get to that (no spoilers in this review).
It starts off with the Enterprise arriving on the scene of a derelict ship: the Brattain. The Brattain's engines have no power, and all its crew are dead (save one, who only has a single vital purpose for the plot) -- it turns out they killed each other. The Brattain's logs indicate an increase in paranoia and erratic behavior in the weeks leading up to everyone's demise. What happened?
The lack of power to the engines is also a mystery. Geordi says everything should work, but nothing does. They decide to put the Brattain in tow, but then the Enterprise starts experiencing engine problems, as well.
The crew also starts to have issues with aggressive behavior, hallucinations, memory loss, and the like. Even when Crusher discovers the cause, there isn't anything they can do about it. Meanwhile, Troi is having nightmares about floating through space and hearing voices. And as Picard realizes that he, too, is not immune, he confides in Data that he may be the one crew member that can keep them from ending up like the Brattain.
All this sets up for a nice, tight resolution to the mystery, but there are also some neat little touches along the way. For example, as the days progress, Troi's hair looks more disheveled. Picard looks visibly older. Crusher fumbles in search of her communicator pin. They sell it. And we buy it.
This is an all-around enjoyable episode. It's everything that's good about Star Trek, rolled up into a suspenseful hour-long episode. Easily one of the best of the season, if not the series.
