This is a good tale of romance during World War 2, with a little humour here and there. (Any film with Alistair Sim in it, albeit only for brief appearances, is worth a viewing). It is particularly interesting because of the amount of location filming in immediate post-war London; there is, unsurprisingly given the title, a fair amount of railway coverage including a chase across the lines leading into Waterloo Station. The actors must have had to mind their steps to avoid the live rails!
Unfortunately the print quality is quite poor, with scratches, marks, and fairly poor definition when viewed on a 32" television. Yes it is an old film, but it is a shame a better print couldn't have been obtained.
Still, definitely worth a watch.