Star Trek: Gateways, book 03 : Doors Into Chaos
Robert Greenberger2001

More than 200,000 years ago, the ancient Iconians created a network of interdimensional Gateways providing instantaneous transportation across unimaginable distances. Once known as the "Demons of Air and Darkness," the Iconians mysteriously vanished many millennia ago, never to return – or so it was believed.

Summoned to an emergency briefing at Starfleet Headquarters, Captain Jean-Luc Picard is stunned to discover that the legendary Iconians have returned at last, and are offering to sell the secrets of their advanced technology to the Federation. To prove their sincerity, they have reactivated their long-abandoned Gateways, but the results have been strife and chaos throughout the entire Alpha Quadrant. Now Picard and his crew must contend with feuding Klingons and Romulans as the captain seeks to discover the sinister truth behind the Iconians' unexpected rebirth!