This film centers on one career girl's rise to success, and the unconventional road she took to get there.
Melanie Griffith is Tess McGill, a secretary trying to get ahead at her Manhattan financial conglomerate by taking night classes, reading everything she can get her hands on, and enduring the too-often falsely dangled opportunities of her superiors. After escaping yet another demoralizing set-up, she is reassigned to the company's new mergers executive, the first woman she's ever worked for, Katherine Parker (
Sigourney Weaver). Katherine assures her that their relationship is a two-way street, and offers Tess her mentorship.
Tess is delighted by the feeling of finally getting somewhere much to the chagrin of her boyfriend, Mick Dugan (
Alec Baldwin), whose main ambition is to buy his own fishing boat and doesn't understand the time Tess spends in speech and management classes. Tess presses on, despite Mick's indifference and the bewilderment of her best friend Cyn (
Joan Cusack), who is engaged herself, and doesn't understand why Tess doesn't just marry Mick, already. Tess observes Katherine's style, ease with power and smooth handling of the lecherous men that seem to populate their world. One day Tess decides to come to Katherine with her idea of how their company can help one of it's clients, Trask Industries. While Trask has expressed interest in acquiring television stations, Tess points out that based on what she's read in various publications, Trask would be well served to acquire radio instead. Katherine carefully quizzes Tess on the genesis of this idea, and once she's convinced it really is Tess' own, sends her on her way with assurances of bringing it up at the next meeting. Tess is elated.
As Katherine prepares for a getaway ski weekend with her estranged boyfriend, Jack Trainer (
Harrison Ford), she confides to Tess that she's sure this is the weekend he'll pop the question. Katherine learns that Jack can't join her skiing, but decides she should have a good time anyway ... and promptly breaks her leg. She calls Tess with a flurry of instructions: invitations to answer, people to inform and asks her to take care of things at her parent's house in New York as well. She apologizes for leaving such a mess, but reassures Tess that she can "make it happen."
Tess arrives at Katherine's family's very elegant townhouse and enjoys soaking up the life she wants for herself. She sits at Katherine's make-up table, uses her exercise equipment, and in lieu of speech class, plays and imitates recordings of Katherines very upper-crust cadence. It's in this moment that she runs across a memo Katherine recorded for herself about Tess' idea for Trask Industries. She checks Katherine's home computer and, sure enough, finds more evidence that Katherine is intending to run with Tess' idea all the while passing it off as her own.
Tess returns home, crushed at Katherine's betrayal only to find Mick engaging in a worse betrayal with another woman. Having nowhere else to go, she flees back to Katherine's house. Cyn brings Tess her clothes from the apartment and begs her to please speak with Mick. Tess has decided to take action. She sees Katherine's invitation for a party that night from Dewey Stone & Company, the same company that Katherine had intended to bring in on the Trask deal. In a bold move, Tess sets up a meeting for the following morning with Jack Trainer of Dewey Stone (the radio expert that Katherine had mentioned in her memo) and accepts the invitation to the party herself. She and Cyn go to Katherine's to get ready for the party, and at Cyn's suggestion to calm herself, she takes one of Katherine's Valium. With Cyn's help, Tess remakes herself and attends the party looking different, but still slightly out of place.
Once at the Dewey Stone party she realizes how remote her chances are of finding Jack Trainer and getting a head start with him before their meeting, and has decided to leave when a handsome stranger approaches and asks her to stay for a drink with him. Tess asks the stranger if he knows Jack Trainer, and, of course, the stranger is Jack Trainer, but conceals his identity. After a few drinks, Tess realizes how intoxicated she is and says she must leave and asks the stranger to please get her coat for her. He brings the coat to an incoherent Tess in a waiting cab, and instructs the driver to take them to his place. Once there, he carries the now totally unconscious Tess up to his apartment, realizes the futility of offering her tea, and puts her to bed.
The next morning Tess awakens thinking the worst, and moves as fast as she can to get out of the apartment before having to deal with the sleeping stranger beside her. She escapes with seconds to spare, and regains her focus for her upcoming meeting at Dewey Stone. Draped in one of Katherine's stunning suits, she quickly realizes that the handsome stranger from the night before was Jack Trainer. He and his colleagues praise her idea for Trask's acquisition of a radio network, but are curious why (1) she's come to them, and (2) has no briefcase. She gives them a plausible story on both counts, and they agree to meet further within their company and will let her know if they can be part of the deal.
Back at her, no, Katherine's office, Tess is cursing her bad judgment concerning men and alcohol and Cyn is cursing the double life Tess is leading, warning that she'll be out of not only her man and her home, but her job as well. Suddenly, Jack Trainer appears on the floor asking to see Tess. Tess convinces Cyn to pose as her secretary and meets with Jack. After Tess' questions about the previous night, Jack assures her that nothing untoward occurred, and that Dewey Stone is ready to proceed on the Trask deal. He gives her a gift of a new briefcase to celebrate. Trainer offers to take Tess out to dinner to continue the celebration, but despite her attraction to him, she declines.
Now the frenzy of activity kicks into high gear: Tess playing her role as Katherine's secretary for Katherine when she calls and for everyone else at her company, and the role of deal manager when she's with Trainer. They work well together, making it fun and flirty when they can. When Tess attends Cyn's engagement party, she realizes how much she's changed in a short time, how she no longer fits into the world she once called home, and after Mick's impulsive marriage proposal, says good-bye to him for good. After a successful meeting with Trask, Tess and Trainer sleep together for the first time. Trainer confesses to Tess that he has a girlfriend, and for him it's over, he just hasn't told her yet. Tess' disappointment is evident when she learns the mystery girlfriend is Katherine, and decides to keep her identity as Katherine's secretary a secret.
Everything begins to come to a head: Katherine is returning to Manhattan the same day Tess and Trainer are scheduled to finalize with the principals of the Trask deal, including the owner of the radio network that Trask is acquiring. Tess quickly cleans up and moves out of Katherine's house, dry cleans all Katherine's clothes, and meets her on the company's helipad. Katherine wastes no time drafting Tess to help her unpack, bathe and change so that she can reconnect with the man she is so sure will propose to her. As Tess is about to leave on an errand, Katherine mentions the memo Tess found that started the whole chain of events and points out that it looks like she's proffering the Trask radio idea as her own. She claims that it was a necessary measure, since once Jack was accused of stealing another's idea. Katherine calls Jack over, and after a brief moment he leaves without telling her about Tess. Tess returns from the errand and accidentally leaves her agenda on Katherine's bed. Katherine reads Tess's schedule for the last couple of weeks and becomes enranged.
Before entering the boardroom to finalize the Trask deal, Tess quickly asks Jack if he's ever had any ethical problems about looking over the work of others -- he says he hasn't. The two confess their love for each other and sit down at the table. Suddenly, Katherine, on crutches, bursts into the room screaming that Tess is an imposter and merely her secretary. All the deal participants, including Trainer, are confused and Tess leaves the meeting in shame.
After Cyn's wedding, Tess returns to her company office to clean out her desk. In the lobby, she runs into Katherine, Trainer and Mr. Trask. The women confront each other, with Katherine again accusing Tess of being a thief and liar, and Tess claiming that Katherine is the one who stole her idea. While Katherine cautions Mr. Trask to ignore Tess, Tess asks if Katherine has told him about the potential dealbreaker. Trask is stunned to hear Tess explain the potential hole in the deal, and realizes she may be telling the truth. Trainer manages to maneuver himself, Tess and Mr. Trask into an elevator, and Tess explains point by point how she first conceived the idea for Trask to acquire radio, and shows him the newspaper clippings that inspired her. When the elevator door opens again, Trask confronts Katherine and asks where did SHE get the idea for the deal? When it's clear that she cannot (and will not) provide an answer, she haughtily stalks out of their lives. Trask then offers Tess a job at his firm, but only if she promises to bring the passion and integrity she brought to his deal.
Tess leaves her much better man at their much better apartment to start the first day of what she hopes will be her much better job at Trask Industries. She's directed to an area, and sees an empty secretary's cubicle outside an office emanating energetic phone conversation. She's a bit deflated by the idea that she will be starting at ground zero again. She's then confronted by the person from the office who profusely apologizes for being in her, Tess', office. Tess is pleasantly amazed. She settles into her new digs and makes her first call to Cyn asking, "Guess where I am?"