Don DeLillo's novel Falling Man is the story of one man's journey after he survived the terrorist attacks in New York City on September 11, 2001. Keith was in one of the towers when it was hit by an airplane but managed to get out before it collapsed. This is obviously a traumatic event which is likely to impact him for the rest of his life. Your question asks how he changes after the incident, and here are a few specific examples of change in Keith:
- He was living in his own apartment, separated from his wife, before the attack; afterward, he goes straight to his former home and from then on lives with Lianne and his son Justin.
- He was not a particularly good husband before the attacks, often angry and combative; after the attack he knows he must work on not being so angry and goes to the gym to do that.
- He was an "office guy" when the towers were hit; after the attacks, he tries to do that again but finally settles into a career on the road playing poker for a living.