Amusing little British comedy that has rural mailman Harold Petts, Spike Milligan, transfered from his sleepy little country town post office where everything has been the same as it was for hundreds of years. Harold's father grand-father great-grandfather great-great-grandfather etc, etc. were also mailmen, to the large and bustling London GPO (General Post Office) where sorting and delivering the mails is a lot lot more complicated modern as well as mechanized.
As soon as Harold steps off the train he get's involved in an attempted mail robbery that, even though he thwarts it, he's somehow suspected of masterminding just for his being on the scene of the crime and recovering the stolen mailbag. Not at all familiar with the workings of the modern industrial world Harold get's involved with pretty modern artist Jean, Barbara Shelly. Jean not only gives Horald directions to his new job at the London GPO by taking the tube, or subway, but also sets him up for a place to stay, until he finds a place of his own, in her attic.
Getting to his job at the post office Harold at first has trouble in delivering the mail since just one high-rise building, of about a dozen, on his route has as many if not more mailbox's as the entire town that he comes from. This causes him to oversleep and come in late for the work the next day the first he was even late on the job in fifteen years. Harold is still suspected by the police as being a criminal master mind who's job in the post office is just a cover to rob it as well as him being suspected by a local gang of clumsy and butterfingered hoods, headed by the not so bright Rupert ,Warren Mitchell, as being the same thing; a criminal master-mind posing as a klutzy and buffoonish mailman to throw off suspicion.
Finally getting the hang of his new job, as a big city postal worker, Harold suddenly starts to improve and accelerate his working habits. It's later that Harold causes a new mail-sorting machine, that can do the work of six mail distribution clerks, to short-circuit and break down In it just trying to keep up with him sorting letters by hand. Whats even more remarkable about this superhuman feat on Harold's part is that his job isn't even that of a mail distribution clerk but a of mail carrier!
Later in the movie Harold gets Jean a job at the post office, since she wasn't at all that successful in selling her modern art paintings, so she can pay her bills. It's that very good deed on Harold's part that causes both the police and the Rupert Mob to think that he and Jean are planning to rob the post office, via an inside job, of some 2 million in Pound Sterling thats to be processed through the very post office that both Harold and Jean are now working at. That's when the real slap-stick Keystone Kop, as well as Keystone Postman, fun and action begins in the movie "Postman's Knocks".
You have to stagger or sleep-walk through, like Harold did, most of the film to really get a good number of belly laughs when the action starts to really pick up with Harold and Jean running through the main post office with the Rupert mobsters and fumbling London Bobbies chasing them as all hell breaks loose in that giant mail room. Hraold & Jean Wracks the entire GPO and thus bringing the delivery and processing of the mail back to the 18th Century. Harold has in the end not only singled-handled foiled a major mail robbery but got himself a promotion as post master, of his little hometown post office, and married his girlfriend Jean. On top of everything else Harold also saved the jobs of countless postal workers, or mail distribution clerks. Harold that this by his being able to keep the new and modern $400,000.00, or 150,000. Pound Sterling, mail-distribution machines from taking over their jobs with his lighting-like mail boxing seed, causing them all to break down in trying to keep up with him.
P.S It looked like the scene of Harold competing with the mail-sorting machine was taken from the Charlie Chaplin 1936 silent-film, even though talkies were already around for almost ten years at the time, "Modern Times". Unlike Charlie Chaplin in "Modern Times" Spike Milligan or Harold Petts in "Postman's Knocks" showed that good old fashion man CAN prevail over modern and unemotional automation not the other way around.
