From the back of the booklet:
"Attention, Troubleshooter! Your friend The Computer has just discovered a previously unsuspected network of hidden rooms, tunnels and access vents that interpenetrates all inhabited sectors of our beloved Alpha Complex. This is perfectly normal and nothing to worry about. Do not be alarmed by those sirens.
The Computer politely requests you to explore these dark, treacherous tunnels immediately, and to shoot all mutants and traitors you might bump into. Rejoice, for The Computer has also sent Internal Security and Armed Forces squads into these same tunnels, with clear instructions to shoot everything that moves! Don’t you feel safer now?
When you file your accident reports, please refer to this hidden tunnel complex as...
A PARANOIA location sourcebook by PAUL BALDOWSKI
Illustrated by JIM HOLLOWAY
The Computer runs Alpha Complex perfectly, of course. If it should occasionally wall off a contaminated corridor, or block access to a few dozen mutant-haunted subsectors--well, picky picky. Bureaucrats erase those areas from the maps, and no one ever thinks about them again--no one by the thieves, refugees, unpersons and mutant atrocities of the Underplex.
In these dark, sprawling tunnel networks, traitorous secret societies hide their most dangerous evidence. Intrepid ‘urban infiltrators’ defend it to the death. Good thing the Troubleshooters have the new equipment, specialties and contacts introduced in this 48-page sourcebook, and a campaign kickoff mission to test their mettle (or whatever Troubleshooters have that passes for mettle).
The Underplex--it all comes down to this!"