In her autobiography "'Tis Herself", Maureen O'Hara says that Errol Flynn was always prepared, always knew his lines, and was a pleasure to work with in the mornings. But he drank throughout the day and by 4pm was in no shape to continue. Even after director George Sherman banned alcohol on the set, O'Hara recalled, Flynn would inject oranges with vodka and eat them in the morning, so that he was drunk by afternoon. O'Hara did all the romantic closeups at the end of the day with a black flag marked "X" to represent Flynn.
Errol Flynn suffered a broken ankle during filming, and while he was recovering, Universal-International took advantage of the unused sets by scripting and shooting a hastily assembled B picture, Il pirata yankee (1952) with Jeff Chandler.
Though Errol Flynn did most of his own stunts, he balked at the one involving sliding down through a sail on a rapier blade, which was originated by Douglas Fairbanks in Il pirata nero (1926). The stunt was performed by a double.
Errol Flynn (I) was already ill with liver disease and hepatitis.
Douglas Sirk spent two days filming additional swordfight scenes while director George Sherman had left to do his next project.