In contemporary Buffalo, Dan's world is upended when he unearths a young woman's skeleton while replacing the gas main in a city neighborhood. Using the meager clues available, he and his archaeologist friends embark on a quest to piece together the mystery of her death.

In 1851, the newly widowed Madeleine Talmadge and her orphaned nieces, Jane and Lydia, seek the aid of a cunning spiritualist, Alexander Dodge Lewis. Lewis leads them on a perilous journey from one séance to the next, attempting to summon the spirit of Madeleine’s late husband and promoting Lydia's latent abilities as a medium. Jane, suspicious of his motives and fearful of his influence, seeks to disentangle her aunt and cousin from Lewis’ beguiling sphere --- with dire consequences.

As the past collides with the present, layers of time peel back to reveal long-buried secrets of loss, love and murder. Alongside its riveting plot, RIDDLE OF SPIRIT AND BONE offers subtle rumination on what can be observed, what can be known, and what can be trusted.