This YouTube playlist covers a wonderful lecture on story structure from Dan Wells. Wells is the author of the fantastic novel I Am Not A Serial Killer, which I urge you to pick up and read. I will, of course, post a full review of the book later.
The lecture is about 50 minutes long in total, but it is well worth your time if you have any interest in writing. There is lots of useful information in this talk, and I know using the approach presented in these videos has certainly helped me in my own writing. If you enjoy the lecture, I would encourage you to also check out Writing Excuses, a weekly podcast on writing that Wells hosts along with author Brandon Sanderson and Howard Taylor.