#5 on a random Guardian list of Ealing comedies. The fictional island Todday in the Outer Hebrides runs out of whisky in 1943. This is relieved by the running aground of a ship carrying 50,000 cases of the stuff. The local home guard is lead by uptight Englishman Basil Radford who wants to prevent the wily (Scots) locals from recovering the goods. He is easily evaded. Somehow Joan Greenwood is deemed the co-lead with Radford despite being only involved in some minor romantic stuff with sergeant Bruce Seton. It's well constructed but pedestrian with a lot of filler between a few genuinely funny bits.
Wikipedia. Somehow it got remade in 2016.