Continuing on theme of key moments and using change to draw the viewer in, have a look at this T-Mobile UK ad:
Note the use of the Dire Straits "I want my MTV" and how things change at the points where Mark Knopfler's guitar kicks in at around 1:34. Then see the changes in the characters. Did you feel the tension building? Did you know a major change was coming with that music change? A well done ad in my opinion.
Last time I wrote about success storytelling. I made a 12 minute video explaining my thoughts on success story videos. If you've made hundreds of success story videos I think you'll find much of this to be basic but you may find the focus on key moments useful. If you've never made a success story video you will want to watch the whole thing and then go look at some good success stories on various company websites or YouTube channels.