One of the last bills signed by President Lincoln authorizes pushing the Union Pacific Railroad across the wilderness to California. But financial opportunist Asa Barrows hopes to profit from obstructing it. Chief troubleshooter Jeff Butler has his hands full fighting Barrows' agent, gambler Sid Campeau; Campeau's partner Dick Allen is Jeff's war buddy and rival suitor for engineer's daughter Molly Monahan. Who will survive the effort to push the railroad through at any cost?