Iron Man 3 with a commentary about actions, reactions, change and what remains essentially the same.
Of the three movies in the Iron Man series, I like this one the least because it took me a while to comprehend the story, particularly the backstory about the villain. When I did, I thought that the theme has een played out before in Spiderman, X-Men and Incredible Hulk. It also seemed that the transformation made those affected unkillable. Their defeat at the end was not believable. Nor was it explained how Tony Stark reversed the process.
Robert Downey is a joy to watch as Iron Man, arrogant yet lovable and charming at the same time. I don't think anyone else can play the part as well. I particularly enjoyed his scenes in the workshop at home and with the kid who helps Iron Man out.
Stan Lee always appears in a cameo in Marvel movies but I did not catch his appearance in this one. Stay until the end credits to see Bruce Banner in a cameo.
PS. In case you didn't realize it, even Tony Stark's choice of sandwich has changed. In Iron Man, shortly after his escape from his terrorist captors, he asked for an American cheeseburger. Here, he asks for a tuna sandwich.