A feisty Quebec trapper meets Arapaho Chief Lame Beaver in his travels throughout the American West. Thus beginning a series of relationships that create a timeline of adventures from the late 1700's to the 20th century. On a trip to St. Louis to sell his wares, he encounters the wealthy silversmith Herman Bockweiss (Raymond Burr) and enters a partnership with him to bring guns and silver to the Indians. He agrees to marry Bockweiss' daughter Lise (Sally Kellerman) and leaves shortly thereafter to return to his trapping trade. He encounters and saves the life of his future partner, Alexander McKeag (Richard Chamberlain), a Scotsman attempting to escape his past. They make their way to an Arapaho camp where McKeag, who has been injured, is tended by Chief Lame Beaver's daughter, Clay Basket (Barbara Carrera). They fall in love, but she instead marries Pasquinel at her father's request. Accompanied by Clay Basket, the partners set out in search of Pasquinel's true desire - gold.

In spite of mounting tensions between the races, Pasquinel, McKeag and the Indians continue a profitable releationship in trading. Clay Basket bears Pasquinel two sons, Jacques and Marcel, while back in St. Louis, Lise gives birth to Pasquinel's daughter, Lisette. Pasquinel continues his obsessive search for Lame Beaver's gold, while McKeag and Clay Basket are secretly in love with each other, but her honor in marriage to Pasquinel won't allow her to reveal it to McKeag.

1845: In Lancaster, Pennsylvania, young Mennonite Levi Zendt heads out west with his bride-to-be Elly Zamm. On the wagon train and in St. Louis they meet young English writer Oliver Seccombe and Army Captain Maxwell Mercy - who is married to Lisette, Pasquinel's daughter. McKeag weds Clay Basket and adopts her half-breed daughter Lucinda. While on the wagon train, guide Samuel Purchase tries to rape Elly, causing Levi and Elly to leave it, meeting McKeag and later establish the settlement of the town Centennial.

Driven by the grief over his wife's death, Levi boards himself up in the desolate cabin once used by McKeag and Pasquinel in their early trapping days. Clay Basket and McKeag soon send their daughter Lucinda to bring him to their home. Eventually, Levi and Lucinda fall in love and marry. Meanwhile, Hans Brumbaugh arrives from Germany to seek gold.

1861: War sweeps the country, the Civil War in the North and South, in the West the Pasquinel brothers, Jacques and Marcel are raiding and murdering soldiers and homesteaders. Colonel Frank Skimmerhorn, an officer in the Wyoming militia arrives in Centennial with intent on killing all Indians.