Lupin's latest pursuit is 500 tons of gold bullion once belonging to the House of Romanov, the former rulers of the Russian Empire. The puzzle he must solve to find it involves an archaic book code, which a cipher machine has decoded as "Bank of Liberty." With Lupin at the center, the undertaking is predictably intricate. The pursuit takes him across the United States and Russia, packed with action and Lupin's classic hijinks.