Sexy female protagonist, an ex-conman turned spy in action-packed shenanigans.

(excerpt from walmart product page, of all places -.-)

Mysterious young heiress Contessa Annika Malikova has been part of Manhattan high society for several years… but if they knew the truth, her dinner companions would faint! The white-haired Contessa is in fact the notorious criminal “BABOUSHKA” — a former Moscow gang leader, now living in exile!But Baboushka’s retirement is about to be shattered, as the US government has somehow discovered her true identity, and blackmails her into working for them! Now she must infiltrate a secret conclave of global crime lords, on a cruise liner, to retrieve information for the Americans. But nobody reckoned on the boat being hijacked by pirates…

This series is currently about 300 pages long.