I won't bang on about the Avengers: Age of Ultron film overall, save to say that I enjoyed it very very much. However, I would like to examine one tiny scene quite a long way into the film, which is an excellent example of efficient storytelling.
Here's the situation: a new character is introduced a long way into the story. Said character is an artificial being in a movie awash with villainous robots bent on destruction. In fact the new character is the creation of evil 'bot Ultron himself. The themes of betrayal, suspicion and switching sides are threaded throughout the movie. The various (Avenger) protagonists have every reason to suspect this android newcomer and bog the film down in tiresome 'how can we possibly trust you?' interplay, consuming minutes of valuable screen time.
So how does the film-maker efficiently subvert that expectation and establish the character's credentials, short of a lame 'No wait, I sense his good intentions' declaration from the nearest empath?
Simple, you let the character casually pick up Thor's hammer and hand it to him.
Perfect. They've already established earlier on that only the worthy can lift the hammer, and even Cap can only shift it a smidge. So simply having the Vision pass it to Thor - without even realising the significance of his action - has this incredible effect both on the other characters and the audience (there was a ripple of collective 'whoa's when I watched the film). He Is Worthy. Now move on.
Excellent use of the existing mythology to keep the story moving forward at a pace.
Also, Paul Bettany in a cape with Thor's hammer. What's not to love.