The greatness of this film lies not with its story, but with the brilliant performance of Michael Caine. In my opinion, this is one of his best, and most underrated performances.A Shock to the System is not a great movie as a whole, but for the most part it is very entertaining. It is a short, well-casted, semi-thrilling movie with a brilliant ending, which is why I’ve given it a generous 3 stars.