Something is wrong with Castrovalva, but the Portreeve cannot help the Doctor identify the problem. And the Master is taunting Adric, caught in his web of power.
As recursive occlusion threatens to destroy everything and everyone in Castrovalva, the Master’s space/time trap is revealed, with Adric at its heart.
When the Sultana happens upon a woman in a rowboat, Dan believes she is a decoy.