In my considered opinion, this is one of the best British comedies of all time (and I flatter myself that I am not usually given to hyperbole). To buttress this opinion, I could mention the fact that the movie is based on (and quite faithful to) one of the most hilarious stories ever penned in the English language (by R. L. Stevenson of "Treasure Island" fame); that the story in spite of its endless comical complications never once becomes too confusing (except of course to Tony Hancock's hapless inspector); and that the story is interpreted by some of the most memorable and talented actors of two generations.
The (then) old guard is worthily represented by Ralph Richardson as the deliciously exasperating Joseph Finsbury, John Mills as the cranky and cantankerous Masterman, and especially Wilfrid Lawson's unforgettable doddering yet stalwart butler (his fellow actor Michael Caine has stated that Lawson is his favorite actor--as well as the favorite actor of every other actor who knew him).
The (then) younger generation, however, does not pale by comparison. Peter Cook's Morris Finsbury sets down a delightfully unprincipled cad (one suspects that Masterman may have resembled him in his younger days), yet we can't quite stop rooting for him, because Michael Caine and Nanette Newman strike just the right sweet and innocent tone as Michael and Julia to make us surreptitiously feel that perhaps they deserve to be cheated out of their money. Moreover, the fact that the fate of the more deserving members of the younger generation is not exactly aligned with the more deserving member of the older generation reinforces the ambiguity--so we find ourselves rooting in turn for Joseph, Morris, and John, then again for Michael, Julia, and Masterman. In this respect, the eventual denouement (which I won't give away) is pleasantly and surprisingly satisfying.
Spare some kudos also for the excellent supporting cast, from Peter Sellers' vacuously venal Doctor Pratt and Dame Cicely Courtneidge's imperious Salvation Army major to such brief but perfect walk-ons as the unflappable engine crew ("We haven't heard the last of this") or poor Hackett's lachrymose widow. This is what British acting is all about.
If, in spite of all this circumstantial evidence, however, I still have not fully conveyed the essential laugh-out-loud, tears-in-your-eyes, still-uncontrollably-snickering-in-church-twelve-hours-later (warning: do not watch this movie if you plan to attend a funeral anytime soon), then I can only say one thing:
Go watch this movie. You'll love it.
