Andy Brewster lives in California and he is traveling the country trying to sell his organic cleaning product Scieo Clean. He makes a presentation to Kmart but the executives do not seem that interested. Andy goes home to New Jersey to visit his mother Joyce and claims he is doing well. Joyce thinks he left home to get away from her but Andy later says he went to UCLA because it had the best organic chemistry program.Joyce doesn't want to go to a meeting of a singles group but Andy wants her to meet a man. Andy's father died when he was eight.While they are still at Joyce's home, Joyce watches an old home movie.Joyce tells Andy that he is named after Andrew Margolis, who she dated when they were in high school. But they went their separate ways and Joyce married Andy's father. No, Andrew Margolis was not Andy's biological father, even though Joyce dated both men at the same time.Andy calls the company that Joyce said Andrew Margolis worked for. He finds out Andrew Margolis is still working for the company, but in the San Francisco office, and that he is single.Andy asks his mother to travel with him. He has several meetings in Virginia, and others in Texas, Santa Fe, Vegas and finally San Francisco (what he doesn't admit is that the final meeting is with her former boyfriend). Joyce points out that Andy's ex Jessica is in Nashville, which is on the way. Andy doesn't want to stop and see Jessica, but things change.When they rent a car, Andy wants an SUV in case of snow but Joyce persuades him to get a small cheap car.Joyce brings along "Middlesex", a book on tape about someone who is neither male nor female. Andy finds it annoying and sometimes embarrassing because of the explicit descriptions of romance.Joyce accompanies Andy to one of his meetings and gives him advice, but she is more annoying than anything else. And she won't put her purse on the dirty floor, but she has a device that attaches the purse to the table. Joyce waits outside, and Andy doesn't listen to the advice, his product is rejected, and Andy tells his mother things went well.When they rent a hotel room, the clerk thinks Andy is getting lucky with an older woman. Andy insists on two rooms and Joyce says two rooms are too expensive, so they stay in one.When they arrive in Tennessee, it looks like the weather will be bad. And it starts snowing. Andy realizes one of the tires may be flat. They stop at a strip club and ask how to get someone to fix the car. One of the dancers knows about cars and goes out to take a look. She finds that there was ice between the tire and the car and the tire is not flat. Since they need a place to stay until the storm passes, Joyce persuades Andy to call Jessica, who comes to pick them up. It turns out Jessica is married to Rob and pregnant, and they live in a nice house. Andy and Joyce have a nice visit where it is revealed Andy proposed to her, which Joyce did not realize. Soon Andy and Joyce are back on the road.In Texas, Andy has a meeting with Costco. He finds out the person he is meeting with will come out to where he is waiting with his mother, so Joyce gets involved with the presentation. The Costco employee Ryan doesn't seem interested in Andy's product, especially after Joyce keeps pointing out problems with Andy's presentation and Andy gets mad. Ryan would like to know how to get what Joyce uses to hang her purse.Andy and Joyce have an argument and Joyce goes to a bar. Joyce is having a good time when Andy tries to get her to leave. Andy gets a black eye from one of the men.Andy and Joyce continue to travel across the desert and Joyce wants to see some attractions. And they have to eat so they stop in Lubbock at a place called Cattleman's Ranch. Andy finally reveals to his mother that he is a failure. After the waitress mentions a huge steak that few people succeed in eating, Joyce accepts the challenge. If she can eat a dinner that includes several pounds of steak in an hour, she eats free. If not, the dinner costs $100. With encouragement from Ben Graw, Joyce is successful. She leaves the restaurant wearing a t-shirt saying she ate that meal. Ben says he was just passing through but was so impressed with Joyce that he would like to spend more time with her. His business will include a trip to New Jersey. Joyce isn't that interested, but she does take his number.Andy and Joyce stop at the Grand Canyon.In Vegas, Andy and Joyce check in at a nice hotel. Joyce goes to the slot machines and wins enough to get her ears pierced. She already bought frog earrings.The next day Andy makes his presentation with host Amy to Home Shopping Network, which is recorded. The executives are bored and Andy sees Joyce and is reminded of the advice she gave him. Andy asks Amy and the others about their families and reminds them how much safer his product is than other cleaning products. Joyce had suggested actually drinking it, which Andy does. The executives are very impressed.Joyce wants to stay behind and have more fun in Vegas, but Andy has to confess that he has no meeting in San Francisco. In fact, the meeting is for his mom, with Andrew Margolis. This upsets Joyce but she agrees to go along.Andy has found out where Andrew Margolis lives and he and Joyce go to the house. A young man answers the door and thinks they are trying to sell something he doesn't want. Andy asks the man about his father and the man says his father died but did run the company he works for now. His name is Andrew as well. Joyce is upset to learn that Andrew Margolis died but happy to see everything Andrew Jr. has to show him. However, Andrew Jr. says his father never mentioned Joyce and that his mother is in Florida. Then Andrew's sister walks in with the mail. Her name is Joyce. This makes Joyce Brewster very happy because it means Andrew never forgot her.At the airport Andy and Joyce turn in the rental car after the narrator reads the ending of the book. Andy and Joyce go their separate ways. Andy sees as Joyce makes a call on her cell phone and thinks she can't wait five minutes to call her son, but the call is to Ben.