I almost gave up on this film after the first hour. It was just too slow for me and I was having difficulty picking up some of dialog with the foreign accents (no subtitles are offered on the DVD).
However, once the "invasion" started the film was very interesting. The only ridiculous part was the role played by Larry Hagman. Liberal Hollywood loves to portray every Southerner as a gung-ho, out-of-control military freak. If I was from the South, I would have been highly offended at this stereotype.
What's really different about this film is that it's a World War II story told from the German side where the Germans are pictured as humane people. You don't see that too much from English-speaking filmmakers.
Michael Caine is the most likable of these people, one of those given the assignment of kidnapping Winston Churchill (interesting premise, off the best- selling book by Jack Higgins). Donald Sutherland plays an Irishman recruited to help in the kidnapping and he's fun to watch.
This is really a man's movie, something like "The Guns Of Navarone," but they inserted Jenny Agutter in here to give the viewers a pretty face and some romance, even though it has absolutely no bearing on the story.
Robert Duvall, Jean Marsh, Treat Williams, Donald Pleasance and Anthony Quayle are some of the other "name" actors who contribute. All in all, a pretty good movie if you can get by that first hour!