In the year 1861, just prior to the outbreak of the Civil War in the Colorado Territory, Owen Pentecost (Robert Stack) is a man from North Carolina who comes west to Denver on a whim. He encounters Ann Merry Alaine (Virginia Mayo), who is going there to open a dress shop.

In a Denver hotel saloon, Owen wins a poker game with the owner, Jumbo Means (Raymond Burr), who bet his estate on the last hand. Along with the hotel comes Boston Grant (Ruth Roman), who works there.

Both women begin to fall for Owen. He has money on his mind, specifically the gold of the town's Confederates, which turns out to be what brought him here. But the predominantly Union town wants the gold, and with the Civil War approaching, the town is split. Owen leads the Southerners in an escape attempt with the gold.

• Robert Stack as Owen
• Virginia Mayo as Ann Merry
• Ruth Roman as Boston
• Raymond Burr as Jumbo
• Alex Nicol as Capt. Kirby
• Regis Toomey as Father Murphy
• Leo Gordon as Zeff Masterson
• Carlton Young as Col. Gibson
• Donald MacDonald as Gary John Lawford
• Peter Whitney as Phil the Cannibal
• Dan White as Rogers (uncredited)

• List of American films of 1956
• "Great day in the morning" is a southern expression, e.g., James Brown used it in Get On Up (2014)
• "Great Day in the Morning", a song recorded by such artists as:
  • Hoots & Hellmouth, on the album Salt (2012)
  • The Hoppers, a gospel song on the album Great Day (2003)
  • Brad Vickers & His Vestapolitans
• "Greatdayndamornin'/Booty" (2012), a song by D'Angelo

• Great Day in the Morning at IMDb  
• Great Day in the Morning at AllMovie
• Great Day in the Morning at the TCM Movie Database
• Great Day in the Morning at the American Film Institute Catalog