Three years after the blackout. The children are entering the second phase of their development. Susannah notices changes in their behaviour and makes a terrifying discovery. Her worst fears are realised when a forgotten mother emerges.

With Susannah ostracised, the children's hold on Midwich strengthens. When Paul awakens to the children's true nature, he pleads with Susannah to try to forge a truce with them. Meanwhile Zoe and Sam are galvanised into action by another miracle.