Diegesis This

In L.A. Confidential a surprise moment was when the police chief shoots Jack after tell him about finding the dead bodyguards body under the old woman's house, where as suspense would be waiting for the gun fight to begin at the end of the movie. Surprise moments are usually loud, to catch the audience and the characters off guard, that is the meaning of surprise after all. Another example is when Cora is trying to kill her husband, in The Postman Always Rings Twice, and a cat jumps onto the electrical wire outside the house blowing the power out. And suspense was being built during the car ride to attempt to kill her husband again, this time driving to a cliff and getting him drunk to make it look like an accident. Often Suspense is when you know something is gonna happen, or have an idea of what's going to happen, and the scene slowly makes it's way to that conclusion putting the audience on the edge of their seat to seat what they thought come true. There are rare occasions where suspense is being built and suddenly a surprise twist will happen and change the films path.

Non-Diegesis is sounds or music that come from Narrioation, or music which doesn't come from the film's world and can not be heard by the characters.  Non-Diegesis examples is when the sappy love music played when Frank Kissed Cora in The Postman Always Rings Twice and also the transition music L.A. Confidential. Diegesis is Sounds or music that comes from the film, like the radio being turned on in the car (The Postman Always Rings Twice) or the Police radio (L.A. Confidential)