In this tense 1915 Nick Carter adventure, a secret summons from the president sends the detective to Washington, D.C., where the theft of top-secret coastal defense plans threatens national security itself. Chief Welden of the U.S. Secret Service explains that trusted engineer Harold Garland discovered his portfolio had been switched with a dummy packet of blank paper, a brazen act that suggests inside knowledge and possible foreign espionage. Nick quickly takes command of the inquiry, questioning Garland with cool precision and reconstructing every step of his journey from Annapolis to the capital. As the investigation deepens, Nick and his assistants Chick and Patsy begin to see that the missing plans, a brutal assault on Captain Casper Dillon, and a web of shady figures may all be connected. Nick's suspicions point toward a carefully coordinated conspiracy involving Margate, Carney, Trent, the enigmatic Irma Valaska, and Baron Esterveldt. While Patsy is trapped by the criminals, Chick tails the suspects to a hidden refuge and rescues him, bringing the team closer to the truth. But the case turns even more dangerous when Nick, posing as Michael Rohan, confronts Dillon and exposes him as a traitor—only to be overpowered when Irma bursts in with a revolver. Fast-paced, atmospheric, and full of espionage, betrayal, and razor-sharp deduction, this government case pits Nick Carter against a ruthless ring determined to keep its secrets buried. This edition has been fully restored with modern typesetting, custom cover design.