This is a surprisingly efficient rendering of one of many rather unknown but important operations in the second world war, the rescuing of stranded air pilots shot down by Germans and landed in the North Sea. Sea Otters and boats had to search for them in bad weather and stormy seas amid mine fields and over vast areas, and sometimes some could be rescued, even if snatched right out of the claws of the enemy almost getting at them first. This film in addition features some excellent actors in leading roles, like Nigel Patrick as the almost bullying leader of the rescue crew, bu he just had to be like that, Michael Redgrave as custodian of state secrets at peril stranded in a dinghy in the middle of nowhere in the North Sea, with Dirk Bogarde in a critical role as a major security risk among the shipwrecked. The film is partly unbearable, as it doesn't hesitate to give a very intimate insight into the conditions of the stranded on board the dinghy in hard weather night and day on the threshold of death, but it is well worth waiting for the finale. Let's see if you have any nails left after that.