On his wedding night in 1953, in Detroit, Michigan, an unexpected champagne cork incident leaves college engineering professor Robert Kearns (Greg Kinnear) nearly blind in his left eye. Renowned as the automobile capital of the USA, Detroit is home to major car manufacturers like Ford, Chrysler, Jeep, GM, AMC, and Dodge. Fast forward a decade later, Robert is living a joyful life with his wife, Phyllis (Lauren Graham), and their six children.
While driving his Ford Galaxie through a slight drizzle, Robert finds the repetitive motion of the windshield wipers increasingly bothersome due to his impaired vision. He becomes acutely aware that toggling the wiper on and off is necessary; while active, it cleans the windshield, but causes a drag on the spotless glass, and when off, the rain obscures his sight. This realization sparks an idea for a new wiper blade mechanism inspired by the human eye, designed to blink intermittently rather than operate continuously.
After some initial trials, Robert discovers that a mechanical solution won't work to create pauses between wipes, leading him to explore an electronic alternative. With the backing of Gil Previck (Dermot Mulroney), who runs a car dealership, Robert transforms his basement into a makeshift laboratory. Here, he develops a prototype and tests it in a fish tank, aware of the vast potential—20 million cars are produced annually in America, all of which could utilize his innovation.
Supportive of Robert's ambition to manufacture his wipers, Gil learns that major car manufacturers are also pursuing similar "intermittent" wiper technologies, with Mercury having worked on it for over a year. He encourages Robert to present his invention to Ford, which shows interest in a meeting. After securing a patent, Robert showcases his wiper to Ford's engineers, who have struggled with a similar design.
When the Ford researchers realize Robert has devised a solution, they are eager to integrate his invention into their vehicles. However, Robert is cautious and demands a fair deal before disclosing the intricate workings of his mechanism. The engineers at Ford inform their higher-ups that Robert’s invention could revolutionize their offerings, leading executive Macklin Tyler (Mitch Pileggi) to ask Robert for a comprehensive business plan.
Despite his efforts and commitments—including renting a sizable warehouse and sourcing parts from Motorola—Robert is left in limbo as Ford pulls support for his project after initially showing great interest. During a Ford dealer convention, he witnesses the Mustang's debut, which promotes the uninterrupted wiper as a standout feature, leaving him devastated—his concept was appropriated without recognition or compensation.
Determined to seek justice, Robert considers legal action against Ford, but Gil hesitates to provoke Ford given their previous lucrative relationship. This turmoil impacts Robert significantly, leading him into despair and ultimately a breakdown, landing him in a mental health facility. After his release, he is determined to fight for acknowledgment of his invention.
Robert's legal battles span years, causing a rift in his marriage and distancing him from his children. Initially, Ford offers a settlement of $400,000, which Robert declines, insisting on recognition of their wrongdoing. As time passes, the offer increases to $1 million, but still without any admission of fault.
When the trial finally commences, Robert decides to represent himself after his attorney, Gregory Lawson (Alan Alda), withdraws due to Robert's refusal to settle. By this time, his ex-wife and children rally behind him, supporting his fight. Nearing the trial's conclusion, Ford offers a staggering $30 million, still failing to acknowledge their wrongdoing. Ultimately, Robert chooses to let the jury decide his fate, who conclude that Ford infringed on his patents while determining the infringement was not intentional. He is awarded $10.1 million, and later triumphs in securing an impressive $18.7 million judgment against Chrysler Corporation as well.
