A failing witchfinder arrives in an East Anglian village in search of work. Desperate for wealth and fame, all he finds is an uncouth local woman accused of killing a pig.

Bannister must travel to Chelmsford with Thomasine to put on a show trial for the Witchfinder General.

Thomasine's interventions have taken them wildly off course and Bannister has to plot a route through Dedham Vale on foot.

The Dedham ordeal has softened his hostility but when Bannister indulges Thomasine by letting her go for a swim, she is snatched and dragged away to a ransacked church.

Thomasine and Bannister’s arrive in Chelmsford but no longer as travel companions.

Bannister fears Thomasine might not make it to Chelmsford alive and she's no good to him dead.