From publisher blurb:
As night falls and the moon’s pale light begins to shine, an aging knight takes up watch on the walls of a humble fort. Silver figures drift through the clearing below, shining brightly amidst shadow and vanishing in the moonlight. The waters of the nearby lake turn black as the darkened sky, but the stars on its surface are not the same as the ones above: these stars are a path of shimmering dust, and a woman shrouded in grey walks them, emerging from the lake to extend her hand to the vigilant knight far above.
This is the true nature of Fort Vigil, humble as it seems by day. The small fort is only manned by a token force and seen as a soft retirement for the honourable Sir Arnhelm, but it is far more than that. Ghosts haunt the fort and its woods, some clinging to purpose and duty, others mad and unable to rest. With the guidance of the oldest ghost of them all, the Medium of the Lake, Sir Arnhelm speaks to each ghost in turn to give them what peace he can. But the Medium struggles to maintain her humanity, and the number of restless spirits only seems to grow.