Once upon a time, King Arthur's knight Perceval went on a quest to find the Holy Grail. Did you know he succeeded? England has kept the blessed cup safe ever since, storing it in the Tower of London under the care of the Keeper of the Grail.

Time speeds on and now King George has gone mad. Prinny is fat and foolish and Napoleon is tucked away on Elba. English society burbles on its merry way, but Sir Sloane Johnstone bows his shoulders under the weight of his responsibilities as Keeper. Bossy Sarah Frampton has her own set of problems to disturb her sleep.

When Sir Sloane agrees to find a missing Fra Angelico painting for Sarah, he mounts his charger, an ornery horse called Grumbler, and sets out to save the domineering damsel. Security at the Tower of London and the Banshee Brigade clutter up the quest, but as surely as Gunter’s serves ices, the Holy Grail could bless a happily ever after. Will it do so for Sarah and Sloane?