Gifted journalist Cass Roberts enjoys her well-ordered life in San Francisco, yet the recent departure of her fickle lover has left her yearning for a man to be her life partner, one who will complement her zest for adventure and her creative spirit. When she leaves her San Francisco coterie of would-be partners and travels to her childhood home in Oregon, she enjoys long afternoons taping her family's stories as recalled by her Aunt Gin and unexpectedly meets Phil, a local man of many talents who arouses Cass's romantic interest.

In the lush Oregon woods, Cass reluctantly begins to open herself to new experiences and to romance. Yet her dreams become ever more disturbing, especially as she learns about a distant relative named Emmeline, who married against her parents' wishes and whose body was never found after the massive earthquake of 1906. This mystery pervades Cass's violent dreams and leads her to challenging adventures and entirely new ways of envisioning her life, her dreams, and her love.

By combining romance and an intriguing mystery, Magnitude 8.3 shares the thrilling tale of one woman's relentless pursuit of self-discovery and of a love to last through the ages.