The Queen's Blade III: Invisible Assassin

A fallen kingdom, a captured queen, and an assassin who could save them both… His queen is the enemy king’s prisoner, but the Queen’s Blade refuses to serve his foe. Unless he slays those who plot against her, however, she will die. Cotti Princes will taste the assassin's blade to ensure her safety and win his freedom, but powerful men plot his demise and that of the infant queen.