An alternate history featuring Haydn and Prince Esterházy, and also a secret society that dabbles in alchemy and worse -- which works.
The main characters are Charlotte, a widow taking refuge with her sister -- the prince's mistress -- and Carlo, a castrato singer and only nominal guest.
It involves the Princess having Charlotte call on her, two runaway lovers, a new opera, a surprising visit, the sweet voice of Charlotte's maid, a foolish lieutenant who made promises while drunk, and more. Somewhat uneven in development.