Londoners Paul and Tricia Feenan sell up to escape to the isolated Holiwell village where Tricia has inherited a property. Scattered throughout the settlement are centuries-old stones used during the Great Plague as boundary markers that the infected weren't allowed to cross. Since then each year the village trustees have insisted on an ancient ceremony to renew the village boundaries, until a misguided act by the Feenans' son then reminds the village that there is a reason traditions have been rigidly stuck to, and that all acts of betrayal, even those committed centuries ago, have consequences.