Willy Loman, an old salesman, returns early from a business trip. After nearly crashing multiple times, Willy has a moment of enlightenment and realizes he shouldn’t be driving. Seeing that her husband is no longer able to do his job as a traveling salesman, Willy’s wife, Linda, suggests that he ask his boss, Howard, to give him a local office job at the New York headquarters. Willy thinks that getting the new job is a sure thing since he (wrongly) sees himself as a valuable salesman.
We begin to learn some family background and hear about Willy and Linda’s grown sons, Biff and Happy. Biff has just returned home from working as a farmhand in the West. Willy thinks Biff could easily be rich and successful, but is wasting his talents and needs to get on track. Willy thinks Biff is being wish-washy to spite him.
Later that night, Willy starts having flashbacks and talking to imagined images as if they were real people. You guessed it. Something is wrong. He’s ranting so loudly that Happy and Biff wake up. The brothers are legitimately worried, as they have never seen their father like this. Biff, feeling as though he should stay close to home and fix his relationship with his dad, decides to talk to a former employer, Bill Oliver, about getting a loan to start a business.
In the middle of the night, Willy’s talking to himself so loudly that everyone wakes up. Linda admits to her sons that she and Willy are struggling financially. Worse, Willy has been attempting suicide. She’s worried and takes it out on her boys, accusing Biff of being the cause of Willy’s unhappiness. Now Willy gets in on the family discussion and the situation goes downhill. He and Biff begin to argue, but Happy interjects that Biff plans to see Oliver the following morning. Willy is overjoyed. Everyone goes to sleep believing that tomorrow will fulfill their dreams: Willy expects to get a local job, and Biff expects to get a business loan.
The next day, of course, everything goes wrong. Willy feels happy and confident as he meets with his boss, Howard. But rather than give him a transfer to the New York office, Willy ends up fired. Destroyed by the news, he begins to hallucinate and, yes, once again speak with imaginary people as he heads out to meet his sons at a restaurant.
Waiting for their dad at the restaurant, Biff explains to Happy that Oliver wouldn’t see him and didn’t have the slightest idea who he was. Distressed, spiteful, and something of a kleptomaniac, Biff stole Oliver’s fountain pen. By now, Biff has realized that he was crazy to think he would ever get a loan, and that he and his family have been lying to themselves for basically their entire lives. When Willy comes into the restaurant demanding good news, Biff struggles to explain what happened without letting his father down. Willy, who can’t handle the disappointment, tries to pretend it isn’t true. He starts drifting into the dreamy past again, reliving the moment when Biff discovered his (Willy’s) affair with a woman in Boston. While their dad is busy being detached from reality, Biff and Happy ditch him for two girls.
Biff and Happy return home from their dates to find their mother waiting for them, fuming mad that they left their father at the restaurant. A massive argument erupts. No one wants to listen to Biff, but he manages to get the point across that he can’t live up to his dad’s unrealistic expectations and is basically just a failure. He’s the only one who sees that they’ve been living a lie, and he tells them so.
The night’s fight ends with Willy realizing that Biff, although a "failure," seems to really love him. Unfortunately Willy can’t get past the "failure" bit. He thinks the greatest contribution that he himself can make toward his son’s success is to commit suicide. That way, Biff could use the life insurance money to start a business.
Within a few minutes, there’s a loud crash. Willy has killed himself.
In the final scene, Linda, sobbing, still under the delusion that her husband was a well liked salesman, wonders why no one came to his funeral. Biff continues to see through his family’s lies and wants to be a better man who is honest with himself. Unfortunately, Happy wants to be just like his dad.