In damp, quiet, coastal Maine, Warren, Joan, and their mother have lost their much-loved father and husband to the unexpected onslaught of cancer. Still reeling from his death weeks later, their mother, mired in grief and desperately unable to resurface, commits suicide.

On This Day, told in Warren's voice, is the intimate story of the aftermath the young siblings inherit. Joan and Warren must acclimate to a new life without parental guidance or the assurance of safety and peace while dodging the sly machinations of family and friends who stand to gain from their tremendous loss. They struggle together to make peace and a life for themselves in a page-turning emotionally harrowing novel that confronts the many faces of grief and memory, family ties, loyalty, and self-preservation.