The first of what became the Ealing trademark series is a delightfully antic caper with a cast including seemingly every boy in post war London. Fascinating use of dour and grim bombed-out city locations behind a balmy and childish (and I mean that in the best possible way) story. Alistair Sim's smarmy character makes a meal of the script's juiciest line: "Oh how I hate adventurous minded boys!"
Finally ticked this off the long list of Ealing films to see and enjoyed it a lot. It is slightly earlier than the famous comedies and has a different tone - the first scene with Alastair Sim is a highlight and prefigures those films though.