As the famous riverboat Le Beau Soleil lazily steams down the mighty Mississippi into the heart of the South, distractions of every sort attempt to pull agent for the Treasury Johnny Stanley away from his assignment. While liquor and gaming are no great temptations, his fascination with Le Beau Soleil's owner, the debonair Frankie Deramus, means Johnny's steadfast denial of his attraction to men is no longer feasible. Johnny fights his lust, but when he must come to Frankie's aid, he can't ignore his urges any longer.
Their passionate love affair falls apart when Johnny refuses to admit two men can be in love. A bitter confrontation between the lovers at a Mardi Gras masquerade forces Johnny to run north. Frankie tries to follow, but the Southern states secede one by one, making it impossible to track Johnny down. The Civil War pits brother against brother and separates lover from lover. When at last the lovers meet again, it's on the battlefield....