Only the Brave

Overview
Cooper is a Union Army officer who after being jilted by girlfriend, Virginia Bruce, volunteers on what could be a suicide mission. He volunteers to go behind enemy lines disguised in Confederate gray as a staff officer to Robert E. Lee. He's to ride to a certain plantation which is a local brigade headquarters and deliberately let himself be caught with maps showing false Union troop positions. Of course, the penalty, then as now, is execution.
Similar
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The Great Locomotive Chase (1956)
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The Colt (2005)
Glory (1989)
C.S.A.: The Confederate States of America (2005)
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