Power Play

The Enterprise picks up a faint distress signal from a moon of Mab-Bu VI, where the USS Essex vanished two centuries earlier. Riker, Data and Troi take a shuttle down, but it crashes in the moon's violent storms and Riker's arm is injured. O'Brien beams down to help, and energy beings take over Troi, Data and O'Brien, while Riker's pain keeps them out of him. Back aboard, the possessed officers seize Ten Forward and hold crew members hostage, including Keiko and her baby. They claim to be spirits of the Essex crew seeking burial. Picard eventually learns that they are really criminals from a penal colony on the moon, banished long ago, who brought down the Essex in an earlier escape attempt. As they begin beaming hundreds more of their kind into a cargo bay, Picard traps them there and threatens to open the bay to space. The entities abandon their hosts and are returned to the moon.