Super Sleuths and the Black Castle - Super Sleuths, #4

The Super Sleuths are back... and so is the evil Prince Igor. In the heavy, warm mist, Mud Town shimmers. Grey buildings frown over the deserted streets. Darkness and silence reign with an iron fist. Even if the inhabitants of Mud Town should stir in their sleep, they would not look out of their tightly shuttered windows. No one wants to be a witness to what is happening outside, no one wants to see the dark forces which are gathering in the deep of the night. Can the Super Sleuths overcome this new threat.
Will Milo, Zelie, Zav, Sofie and Sam take down this new evil from Prince Igor and his motley pirate band?