In New York City, secretary Tess McGill takes the Staten Island Ferry on her way to work at Petty Marsh, a Wall Street financial firm. During the ferry ride, Tess’s friend Cyn presents her with a cupcake for her thirtieth birthday and asks about her plans. In addition to work, Tess says she has a speech class and an emerging markets seminar. She guesses correctly that a surprise birthday party has been arranged for her and agrees to be home by 7:15 p.m. At her desk, Tess changes out of the tennis shoes she wears for commuting and into high heels. She becomes despondent when she learns she has been rejected, yet again, by the company’s “entrée program,” but David Lutz, her superior, suggests she meet with his friend, Bob Speck, who works in the company’s arbitrage department. Tess agrees to the meeting, but when Speck picks her up in a limousine and snorts cocaine in the backseat, Tess realizes he intends to have a sexual tryst and nothing more. Back at Petty Marsh, she complains to the personnel director, Ruth, who discourages Tess’s ambition but offers her one last chance in the mergers and acquisitions department. Tess meets her new boss, Katharine Parker, and is surprised to find that Parker is a few months younger than her. As she goes over some ground rules, Parker tells Tess to dress impeccably and suggests she wear less jewelry. Parker claims she is open to new ideas, so Tess comes to her one morning with a proposal for one of their clients, Trask Industries. Although Trask has been attempting to acquire television stations, Tess suggests they should look into radio networks instead. She explains that owning radio stations would protect the company from being acquired by a foreign competitor because the Securities Exchange Commission (SEC) forbids foreign ownership of U.S. radio entities. Parker likes the idea, and Tess suggests it might help her get into the entrée program if Parker supports it. When Parker agrees, Tess excitedly relays the news to her live-in boyfriend, Mick Dugan. The next day, Parker prepares to leave for a ski trip in the Alps and tells Tess she is expecting a marriage proposal from her boyfriend on the trip. Tess asks what she will do if he does not propose, but Parker argues that she makes things happen in her life and recommends that Tess do the same. Before she leaves, Parker informs Tess that Trask Industries did not respond well to her radio idea. Soon after, Parker breaks her leg on the ski slopes. She calls Tess from the hospital and asks her to take care of her house plants and mail for the next few weeks while she recuperates. Tess goes to the apartment and finds Parker’s tape recorder on her desk. Using the recorded messages to practice her speech, Tess discovers a dictated letter Parker planned to send to Jack Trainer at a company called Dewey Stone about the Trask radio acquisition. Although she has not sent the letter yet, Parker is planning to implement Tess’s idea without her knowledge. Dejected, Tess returns home to find Mick in bed with another woman. After sleeping at Parker’s apartment, Tess calls Jack Trainer and pretends to be an executive so that she can propose her idea for Trask Industries herself. Once the meeting is set up, Tess asks Cyn to cut her hair shorter and dons one of Parker’s expensive cocktail dresses for a Dewey Stone company party, where Tess hopes to have a casual run-in with Jack before their meeting. However, when Jack flirts with her at the bar and Tess asks where she can find “Jack Trainer,” he does not reveal his identity and says that “Jack” already left. Jack encourages her to have a drink with him, and Tess becomes inebriated after one shot of tequila because she took an antihistamine before the party. Seeing her colleagues from Petty Marsh, Tess flees and Jack follows her into a taxicab. She is too drunk to recall Parker’s address, so he takes her back to his apartment. Tess awakes in Jack’s bed the next morning and sneaks out. Later that day, she goes to her meeting at Dewey Stone and becomes flustered when she recognizes Jack from the night before. Tess proposes her idea for Trask, but Jack’s colleague, John Romano, rejects it. That afternoon, Tess tells Cyn that she botched her proposal, but Jack shows up to Petty Marsh, saying he wants to work together and has already found the ideal acquisition target – the family-owned Metro Radio Network. He asks her out to dinner, but Tess says she does not want to get romantically involved as long as they are working together. At Cyn’s engagement party, Mick attempts to make up with Tess and proposes to her in front of their friends. Tess responds with “Maybe,” prompting Mick to storm out and break up with her. The next day, Cyn comes to Tess’s office, begging her to give Mick another chance. Distracted, Tess wonders aloud if she could meet Oren Trask, the head of Trask Industries, by attending his daughter’s wedding, uninvited. They are interrupted by a call from Katharine Parker, who announces plans to return in a week. Later, Tess tells Jack she is going to meet with Oren Trask, but when he accompanies her, he discovers her scheme to infiltrate his daughter’s wedding reception. On the dance floor, Jack helps Tess approach Trask, switching dance partners with him. Tess introduces herself as a Petty Marsh associate and pitches her idea for a radio acquisition, and Trask agrees to meet with her the following week. The morning of their meeting at Trask’s office, Tess and Jack learn that another company has made an offer to buy Metro Radio Network. However, Tess argues that Metro is a family-oriented company and says its owner, Mr. Armbrister, would rather sell to Trask. She promises Armbrister will meet with him in person the next day. Back at his apartment, Jack and Tess and make love. Afterward, she starts to reveal her real job, but a phone call interrupts. Jack admits the call was from a girl friend with whom he plans to break up. When he mentions that the woman recently broke her leg on a ski trip, Tess realizes the girl friend is her boss, Katharine Parker, and rushes out. The next day, Parker returns home and instructs Tess to perform the menial tasks of carrying her luggage and picking up her prescriptions. When Jack comes to the apartment, Tess hides and overhears as he attempts to break up with Parker. Tess accidentally leaves her notebook on the bed, and Parker reads it after she leaves, discovering Jack’s phone number and notes about her next meeting with Trask. Livid, Parker barges into the meeting just after Armbrister accepts Trask’s offer of $68.5 million for his company. Identifying Tess as her assistant, Parker claims Tess stole her idea and feigns a fainting spell. Tess apologizes to everyone and leaves. The next week, Tess goes to Petty Marsh to pack up her desk. On the way out, she sees Jack and Parker enter the lobby with Trask. When Jack refuses to board the elevator with Parker and Trask unless Tess comes along, Trask is persuaded to join Jack and Tess in another elevator. Tess shows Trask her old files with the newspaper clippings that inspired her idea. When they arrive outside Parker’s office, Trask asks Parker how she came up with the idea, and Parker becomes flustered and says she cannot recall. Trask announces that he plans to have Parker fired and asks Tess to work for him. The next morning, Jack helps Tess get ready for her first day of work for Trask and presents her with a monogrammed lunch box. Tess finds her desk outside an office and sits down. However, her assistant, Alice Baxter, informs Tess that the office is hers. Thrilled, Tess calls Cyn from her new office to share the good news.