The sinking of the Titanic, the I-35W Bridge Collapse, the St. Anthony Falls Mill District, and Duluth . . . linking these is a secret history of North America. Three people struggle to kw that history: Tim Malone, humiliated in his career and is losing the love of his life; Jed Bjornstad, convinced that the history will give him closure in his brother's death, and Diane Solquist, a newly ordained pastor whose call is challenged. Guarding that secret history is the organization kwn as the Sisterhood of the Hennepin Chalice. And they really kw how to keep secrets.