"Swallows and Amazons" was a children's book written in 1930 by Arthur Ransome that went on to become one of the best known children's books ever written - although the popularity of it and its many sequels has wained somewhat in the past 40 years. I found the book long, somewhat charming, and ultimately dull when I read it a year ago. The movie has succeeded better than the book by not having the overlong run-time implied by the 360 pages of the original book, and adding in some excitement by replacing barely competent (and barely present) thieves with somewhat more competent and menacing pre-war Russian spies (they moved the date up to 1936). It doesn't hurt that it is (as it should be) filmed in the utterly glorious Lakes District of the U.K. - that alone is a significant selling point for the movie. It's not a great movie, but it was reasonably enjoyable and far better than it had any right to be given the advanced age and drawn out nature of its source material. It even mostly manages to hold on to the simple childhood morality that was part of the charm of the book.