The Turn of Midnight by Minette Walters

As the year turns from 1348 to 1349, the Black Death continues its relentless course across England. In Dorseteshire, the first county to be afflicted, the people of Develish begin to question if they are the lone survivors of this terrible pestilence.

Guided by their heretical mistress, Lady Anne, they wait inside the protection of a moat as their stores dwindle, knowing that when the food is gone they will have no choice but to leave. But where will they find safety in the desolate wasteland their county has become? And how can Lady Anne, a woman without rights herself, grant them the freedom they long for?
 
One man has the courage to find out.

Thaddeus Thurkell, a bastard serf, educated in secret by Lady Anne and risen to the post of steward, takes a band of raw, untested youths in search of supplies and news. As free-thinking and heretical as his admired mistress, Thaddeus makes a compelling leader, and his companions quickly learn to throw off the shackles of serfdom and set their minds to ensuring Develish’s future.

But what use is freedom that cannot be won lawfully? Aided and abetted by Lady Anne, Thaddeus conceives an audacious and dangerous plan to secure her people’s right to determine their fates for themselves. Neither foresees the life-threatening struggle over power, money and religion that follows…

…or the trial for heresy that will imperil all in Develish…