Marianna raids Rusalka's clandestine lab and discovers riddles wrapped in enigmas: a strange undersea base and an even stranger wall-safe. Meanwhile Knox, running interference for her up on bridge deck, inadvertently learns more from a casual conversation than he was supposed to -- if only he could figure out what it was.

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It's back to business, as Marianna drags a reluctant Knox into a raid

on Rusalka's secret lab, while back in DC her boss is planning an

assault on a whole different order of magnitude.

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A day aboard the megayacht Rusalka offers every manner of indulgence, from romance and frivolity, to remembrance and regret.

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Seeking the secret harbored at Rusalka's heart -- with paper, pencil, and force majeur.

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Knox and Marianna's tour of the megayacht Rusalka unexpectedly hands them the key they need to break the Grishin case wide open. As far as Knox can see it's mission accomplished, but Marianna's only getting started, and all the while Rusalka is setting sail ...

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Knox attends the Kennedy Center gala intent upon winding up his involvement in the Grishin investigation as quickly and painlessly as possible, only to find that Marianna has something quite different in mind. Meanwhile, the target of that investigation, Arkady Grishin himself, retires to GEI's fabulous megayacht Rusalka, there to summon up a computer-generated chronogram of recent Russian history, and drink an ominous toast to its might-have-beens ...

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Marianna manages to extricate Knox from the clutches of Russian State Security in the nick of time. But the rescue comes with strings attached ...

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Jack Adler's academic adversaries seek to quash his research via bureaucratic maneuvering. GEI hitman Yuri, however, favors the direct approach.

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Jonathan Knox wanders the halls of the museum and the corridors of his own memories, pondering whether to help CROM, so lost in thought that he fails to notice he's got company.

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Plagued by insomnia, Jack Adler wrestles late into the night with balky equipment and his own doubts -- which means he is there to witness it when his primordial black hole goes flashing across his screens. Is it the greatest discovery of all time, or the greatest danger the world has ever faced?

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