A sector of space surveyed by the Enterprise-D in 2365, whose planetary systems were tearing themselves apart and which contained the inhabited world Drema IV.
The Selcundi Drema sector is the setting of the Next Generation episode Pen Pals.
The Enterprise-D arrives to find out why the planets of several systems there are unusually unstable, some having broken up entirely. Riker gives Wesley Crusher his first command task, leading the team of specialists who carry out the mineral surveys.
Meanwhile Data picks up a faint radio signal from a child named Sarjenka on Drema IV and begins answering it. Her world turns out to be suffering the same upheavals. Wesley's team traces the cause to dilithium deposits in the crust, and the ship uses modified probes to calm the planet, at the cost of bending the Prime Directive.