Book 5 in the Jayne Robinson series.
"As Moscow prepares to invade Ukraine, Robinson uncovers evidence of a Russian plot, masterminded by a mystery Kremlin puppet, to destroy a critical hydroelectric dam. But which one? As the young dam engineer disappears after hearing too much, apparently kidnapped by a dangerous Russian seductress, Robinson finds herself in a desperate race against time down the River Danube to locate him.
Nothing is what it seems: Robinson is forced to take on spiraling risks—urged on by a US President who is preparing for a visit to Kyiv to support his Ukrainian counterpart.
To make progress, Robinson gets involved in a high-stakes game of international poker with a top-level asset inside the Russian president’s inner circle—who was recruited under coercion."