Jumping Jacks is arguably the best of the Dean Martin-Jerry Lewis films, but exactly why is hard to say. The basic plot is hardly original, the kind of mistaken identity, fish out of water nonsense that has been seen in countless films, often with wittier dialogue and fresher variations. Yet for some reason, Jacks' script comes across as "tried and true" rather than "tired and formulaic." Perhaps some credit must go to Norman Taurog, an old, experienced hand at taking familiar situations and milking them for all they're worth; Taurog certainly keeps things moving, and his direction has an air of freshness to it, as if he couldn't help but be amused by the goings-on and the cast that he's working with. Martin and Lewis, also mining familiar territory, really click in Jacks; the chemistry is in high gear, and they each have time to shine individually. Lewis overdoes as usual, but it's tolerable this time, and there are many moments when one sees why he had such incredible appeal for many moviegoers. Martin is in good voice, and has a lot of fun with the ridiculous "Parachute Jump." The supporting cast stays out of the way of the stars, but does what's asked of them. Whatever the reason, Jumping Jacks is a surprisingly good film.