It is 1804--a historic year in America--the year that Meriwether Lewis, William Clark, and the Corps of Discovery set out for their now-legendary exploration of the Louisiana Purchase, departing St. Louis to travel across the country to the Pacific Ocean and back. In this fictionalized biography of the journey based upon the journals of Lewis, Clark, and other members of the team, an unheralded member of the Corps, Seaman, a 150-pound Newfoundland dog, is introduced to young historians. Seaman travels the long journey with the Corps, serving a key role in the expedition's success, catching and retrieving game, and protecting the expedition team from wild animals and hostile Indians. Come along with Lewis, Clark, the Corps of Discovery, and Seaman as they meet Sacagawea who joins the expedition, form friendships with several Indian tribes, survive near-death encounters, grizzly bear attacks, and buffalo bull stampedes through the camp, cross the Continental Divide, overcome the wounding of their seemingly fearless leader, Meriwether Lewis, and rejoice as they return to civilization in 1806.