From the book description:
June 30th, 1908 — In the remote Tunguska region of Siberia, the most violent cosmic collision in recorded history flattened ancient forests over an area half the size of Rhode Island. Yet after a hundred years of international scientific research the cause of this impact remains a mystery.
A MAVERICK ASTROPHYSICIST
Jack Adler thinks he’s fingered the culprit: a submicroscopic black hole, smaller than an atom, heavier than a mountain, older than the stars. What’s more, that fantastic object is still down there, deep inside the Earth, burrowing through the mantle in an ever-decaying orbit that will end only when it has devoured the entire planet.
A ROOKIE SECRET AGENT
Marianna Bonaventure is tracking three missing scientists suspected of involvement in weapons of mass destruction research. The trail leads to Rusalka, the luxurious floating corporate headquarters of billionaire Russian industrialist Arkady Grishin. Determined to prove herself, Marianna creates an elaborate ruse in order to infiltrate the megayacht — a dangerous gambit that requires the coerced cooperation of a rather special civilian…
AN UNCANNY CONSULTANT
Jonathan Knox is one of the country’s most sought-after analysts; his knack for intuiting hidden relationships among seemingly disparate events serves his Fortune-50 clients well. But when Marianna compels the reluctant Knox to join her undercover mission, he must grapple with puzzles of a whole different order of magnitude.
Against violent and cunning opposition, the three of them unearth a scheme to capture the submicroscopic black hole that caused the Tunguska Event and use its awesome power to transform the world — or end it altogether.