In the final year of the 19th century, Peter Winceworth is toiling away at the letter S for Swansby’s multivolume Encyclopaedic Dictionary. But his disaffection with his colleagues compels him to assert some individual purpose and artistic freedom, and he begins inserting unauthorized, fictitious entries. In the present day, Mallory, the publisher’s young intern, starts to uncover these mountweazels in the process of digitization and through them senses their creator’s motivations, hopes and desires. More pressingly, she’s also been contending with a threatening, anonymous caller who wants Swansby’s staff to “burn in hell.” As these two narratives coalesce, Winceworth and Mallory, separated by 100 years, must discover how to negotiate the complexities of life’s often untrustworthy, hoax-strewn and undefinable path.