A young and ambitious Staten Island secretary, Tess McGill, commutes to her job in the high-powered, male-dominated world of Wall Street finance, wrestling with casual sexism and a lack of respect despite her evident acumen and aspirations. After being betrayed and bypassed by her boss, she gets a temporary secretarial position for the savvy and powerful investment banker, Katharine Parker. Tess presents Katharine with a clever business idea, not realizing that Katharine intends to pass it off as her own. However, Katharine's sudden skiing accident gives Tess an unexpected opportunity.

Seizing the chance during Katharine's recovery, Tess collaborates with investment broker Jack Trainer to develop her original idea, under the guise that she is representing her boss. As Tess navigates the complexities and deceptions of corporate life, she and Jack become romantically involved, complicating matters further. Tess's ingenuity and tenacity drive her forward, and she must maintain her ruse while working in a world where a woman's ambition is often met with resistance.