Attack on Titan. Book 5

The Recon Corps, with Eren's help, managed to capture a mysterious female titan. Finally, the fighters learn who has been opposing them in the guise of a deadly giantess. Before they can properly cope with this shock, humanity encounters a new mystery – the secret of the great walls turns out to be no less shocking. And in the midst of general confusion comes news that is capable of shaking the human world imprisoned within the walls to its foundations.