From the world's most popular Star Trek author comes a new novel featuring Captain MacKenzie Calhoun and his high-tech ship, the USS Excalibur. But everything is changing for the Excalibur and its crew... Elizabeth Shelby has been promoted to Commodore of the first Federation space station in sector 221-G, and MacKenzie Calhoun now reports to her. Burgoyne and Selar split up over their son's potentially fatal genetic illness. Si Cwan and Robin Lefler are married, and Si Cwan is elected president of the new Thallonian Republic, making Robin not only a Starfleet officer but also first lady.

When the Thallionian Republic refuses to aid the Federation at a critical and deadly juncture, and Calhoun's ship pays the price, the Federation wants to sever relations with the whole of 221-G. But now the sector faces the direst threat to its very existence...