two men go to war be a base on fact ww2 story about a couple of disgruntled british army dentist who decide to invade france and cause havoc among the enemy . purloin a load of hand grenade and the pair go awol and travel down to cornwall and where they steal a boat . set off for france in the dead of night and the sequence of shot feature the hotel where they have stay and the harbour they be depart all pick out with practical light blaze through the hotel window and other bright light string all around the harbour wall . this and in wartime blackout britain and on a coastline face enemy occupy france and in water regularly patrol by german e boat . another commenter in this section state that the lighting be authentic in that the cornish local at the time figure that a they have never be attack before and there be no reason to assume that they ever would be attack then or in the future . however and even be this be true and the script should have make reference to this hard to believe fact in dialogue and simply because the situation be so unusual and would have breach the strictly enforce wartime regulation concern the blackout . usually in movie and such blackout light and consider a story authenticity and would be restrict to moonlight effect only . another oversight in the film be the lack of anti shatter window tape which criss cross every pane of glass in britain during the war . it hard to believe that this glaring error go unnoticed by cast and crew . i suspect someone in authority say and oh and they will never realise and and simply let it go .