Darkness Hidden

Against all odds, Mio, Jack and Shinobu have defeated the terrifying Nekomata and got home alive. But Mio is still compelled to protect the katana, and now the Underworld has spawned a worse monster - one carrying a devastating plague that sweeps through London like wildfire. As Mio struggles to protect the city and control the sword's deadly powers, she realizes that this time there is no way she can keep everyone she loves out of the line of fire.