"Hidden Empire" (Tom Doherty Associates Book, 335 pages), by Orson Scott Card.

A favorite among sci-fi readers and video gamers, the prolific Orson Scott Card has taken on a topic closer to real life than usual — and with more of a Christian tone.

Set only a few years in the future, "Hidden Empire" is an engaging, if not finely written, parable about heroism and history and Christian faith.

On the assumption that the U.S. can and should direct the globe's political economy Card explores how a domestic monopoly on power could be used to shape the transition to a "post-oil world." But he takes a pass on the modern challenge of terrorism, selecting instead a virulent and lethal virus (with parallels to ancient Rome and to the 1918 influenza epidemic) as his lead character's nemesis.

That character, President Averell Torrent Torrent, a historian who came to power following a rebellion and mass assassination, imposes a quarantine on the entire continent of Africa after the virus appears there in humans. People close to Torrent, including Cecily Malich, a presidential adviser and the widow of the hero who defeated the rebellion, worry about Torrent's intentions. But they stand by him: In Malich's world, heavily shaded by her Catholic beliefs, loyalty is a top virtue.

When Card finally gives in to the moral ambiguity of reality, the book's Christian themes gain strength. Many readers may even forgive his earlier potshots — whether at the science of global warming or the self-involvement of neoconservatives.

Card calls into question the American notion of bravery by having Malich's son show how it conflicts with the kind of faith she has encouraged at home. Loyalty and heroism may be good, the son argues, but helping others is better, and caring for the sick and defending compatriots most noble of all. Malich, cast as a liberal of sorts, starts squaring her conflicting personas of wife, mother, believer and Washington insider to do what she believes is right.

"Hidden Empire" is a sequel to "Empire," published in 2006. Card is known for his award-winning science fiction, including the "Ender" series.