Cities never shed their pasts. They are marked by their histories. You do not walk through them and remain wholly in the present.

In 1966, as the war in Vietnam escalates, twelve-year-old Holzli Lloyd's family moves to Switzerland where his father is a cultural attaché with the American consulate, a job that seems to have hidden dimensions.

Transferred from a village public school to an international school in Zürich, the boy meets Mark, who claims to have visions of the sixteenth century, the time of the Swiss Reformation. Mark tells of meetings with a girl named Regula, whose Anabaptist family is being persecuted by the authorities.

Holzli is intrigued with the Anabaptists' refusal to resist evil and becomes obsessed with finding out whether the stories are true. When the visions take a dangerous turn, though, he is led to intervene-and sees the cost of intervention.

Though Regula deals with political and religious themes, it is more concerned with exploring the limitations of interpretation and judgment.

William S. Kerr's novel The Shield that Fell from Heaven was named to Kirkus Reviews' Best of 2011.