In World War II, the greatest threat to the British Navy is the German battleship Tirpitz. Being anchored in a Norwegian fjord, it is impossible to attack it with any chance of success. But the Navy trains a special commando to attack it, using little submarines to plant underwater explosives under it. Movie Trivia The watch on Commander Fraser's (Sir John Mills') wrist is the famous Jaeger-LeCoultre Reverso, a watch with a case that can be turned around so that the front faces downwards, thus protecting the glass from hard knocks. This robust watch is nowadays considered as an ultra-luxury item. Operation Source, the real life mission on which this film was based, was actually considered a failure in many respects. The Germans easily repaired the damage to Tirpitz. Historians William Garzke and Robert Dulin remarked that the successful repair effort was "one of the most notable feats of naval engineering during the Second World War." This movie was the sixth most popular movie at the British box-office in 1955. The success of this movie caused Sir John Mills to be voted the most popular movie star in the U.K. that year. In the scene where Lieutenant Tom Corbett (Donald Sinden) and his crew first board the midget submarine, the view of three Castle-class frigates tied alongside each other can be clearly seen in the background, this view of the three frigates was also seen in "The Cruel Sea (1953)," when Ericson and Lockhart first take charge of the factitious H.M.S. Saltash Castle after they survive the sinking of their first ship H.M.S. Compass Rose. If you have watched this movie, what would your rating be on a scale of 1 to 10?   My reviews will be based upon 1 to 10.  With 1 being the lowest and 10 being the best.  This movie has a rating of  9.1  out of 10. 𝓜𝓞𝓥𝓘𝓔 𝓡𝓔𝓠𝓤𝓔𝓢𝓣:    If you have a movie request that you would like to watch please let me know in the comment section of the movie.  If I have it or if I can get it, I will upload it for you.