Anecdotes

Three ex-Navy MTBs were used to play the part of 1087. After filming, one of them, ex-Polish Navy S-10 really was used for smuggling and it eventually sank in the Mediterranean. The story is told by the Captain, Hugh Edwards, in his book "Midnight Trader".

The Quayside scenes were clearly filmed at Poole Quay and the wharf opposite.

Additional locations are Portchester Harbour when they pick up the boat, Portchester Castle is in the background, and what would become Port Solent Marina in another shot. When they tie up the boat at the end of the war, this is Portsmouth Harbour, you can clearly see Portsdown hill in the background with the exposed chalk pits.

Uncredited theatrical movie debut of David Langton (Man in Coastal Forces Club Bar).

David Langton had appeared in a starring role in 1937 in the film Alibi Breaker aka Double Exposures under the name Basil Langton; he later changed his name to David, as there was another actor called Basil Langton.

Assistant director Christopher Barry expressed regret that he was credited as "Chris" for this movie.

Speaking in Christopher Barry: Director (2010), he recalled: "I was devastated. They hadn't even bothered to ask me what I wanted to be known as. I mean, everybody called me Chris, it's true, but personally I've always called myself, professionally, Christopher Barry. And er... well, it er humiliated me for a long time. I made damn sure after that I was always Christopher Barry."