During filming, Lauren Bacall was brought to the set in order to gauge her chemistry with Humphrey Bogart with whom she would soon be co-starring in To Have and Have Not. This was the famous duo's first meeting, though it would be months before their romance began.
The plane shown attacking the freighter is an accurate model of a Focke-Wulf 200 (except for the fact that it was shown to have a bomb bay, which it didn't have), a bomber developed from a airliner.