4.) Within the film
Double Indemnity it is difficult to pick out a true hero. There is definitely some lead way in the character of Walter Neff where his actions could have justified him as the hero, but all characters including him have a "tragic" flaw to them. I believe that there is no hero within this film, however I do think like in the play Macbeth there is a tragic hero. A tragic hero is defined as a literary character who makes a judgment error that inevitably leads to his/her own destruction.
In this case Walter Neff is the tragic hero with his flaw being love. Love is a powerful thing that drives his actions and motives in the wrong direction, making him do anything for the woman who has stolen his heart; Phyllis Dietrichson.
This film noir begins with us already exhibiting his wrong doing, as he sits at his desk leaving a message explaining his actions and what exactly happened. Right from the start we already foresee his downfall, and realize he is not a hero. His downfall begins the first time he meets the lovely manipulating Mrs. Phyllis Dietrichson, in her home as he goes over to talk to her husband about insurance. When he sees her, he sees love and possibilities, and naturally begins to flirt and smooth talk her, but when she sees him she sees the possibility of a way out of her miserable life. Her seductive language, and body language tactics persuade him to help her trick her husband into getting life insurance, and then kill him so she receives all of his money. We see Walter's tragic flaw play a factor here as he agrees and formulates a plan to kill Mr. Dietrichson, showing that he would do anything for Phyllis's love. This relationship directly corresponds and relates to that of Lady Macbeth and Macbeth, as Lady Macbeth and her strong persuasion was one of the main causes of Macbeth's downfall, as is Phyllis's to Walter. Walter is bitten by the poison of love which makes him unsuitable for the title of hero, but he relates more to that of tragic hero, which he accepts his role as that shown by his constant realization of his wrong doing.
The overall argument and point of this TEDtalk was analyzing fear, and what we do with it, along with connecting fear to story telling. Karen Thompson starts off the TEDtalk with a story of the Essex whale ship men who are stuck at sea, due to a shipwreck and are forced to assess their options. It is shown that they assess their choices of survival based on the various fears in which they have. The closest island they can sail to has been rumored to be populated by cannibals, to the island of Hawaii they would encounter storms, and the long route of South America they would endure starvation. They end up choosing the South America route because the story that they had in their mind of the fear of cannibals and being murdered was a more vivid picture. Half of the 20 sailors starved to death and some adopted their own form of cannibalism along the way. But this is a clear example of the connection of fear to storytelling. When we are afraid of something we often make up stories of what could go wrong in our minds, like getting on a plane and it crashing, or being murdered by cannibals. We make up elaborate stories in our mind stemming from these fears, and often ask ourselves "what will happen next?" 
The author of this TEDtalk on fear used a lot of pathos targeting our emotions. This is shown through the story of the sailors and us feeling sympathetic towards their situation and the fear that they must have felt and it makes us think of our own fears. Another example that targets the audience more directly so they can better relate is, when Thompson told the stories of her small fears as a child living in California, scared that their chandelier would fall due to the earthquakes. It makes the audience think back to their childhood and the "monsters under their bed" or the small fears they encountered and the stories they made up surrounding that fear. 