Mack, played by Kevin Kline, is enjoying a Lakers game, but his attention shifts from the action on the court to the women in attendance. After the game, he has a conversation with his friend Davis, portrayed by Steve Martin, who delivers an inspiring lecture on how everyone must confront their inner fears. They bid farewell, but on his way home, Mack's car breaks down in a rough neighborhood. With his phone dead, he seeks refuge in a nearby store to call a tow truck. Before help arrives, a group of toughs threatens him, clearly intending to rob him. Fortunately, the tow truck driver, Danny Glover, shows up just in time, helping Mack talk his way out of a dangerous encounter.
As the scene transitions, a helicopter hovers over a house in a troubled area where a son wakes his mother, Deborah, who sacrifices her comfort for the sake of her child. Meanwhile, Mack and Simon share a moment over soft drinks, reflecting on the day's harrowing event and developing a newfound camaraderie. Simon encourages Mack to take a vacation at the Grand Canyon. Then we see Davis back at work, losing his cool as he notices a critical scene is missing from the day’s film shoot.
Next, Mack and his wife, Claire, played by Mary McDonnell, prepare to drop off their son for a month-long camp tailored for the deaf. Simultaneously, Davis finds himself in trouble when a mugger shoots him, leading to an unforeseen hospital stay. The plot thickens as Claire stumbles upon an abandoned baby while jogging, impulsively deciding to take it home instead of notifying the authorities.
At work, Mack, who is a lawyer, navigates the flirtations of his secretary, Dee, played by Mary-Louise Parker, leaving his feelings ambiguous yet intrigued. Simon makes a brief appearance while managing his groceries and remembering a tender moment with his daughter. During a lunch date, Dee confides to her mother about her feelings for Mack. When Mack returns home to find Claire smitten with the baby, they decide to surrender the child to the police.
Simultaneously, Simon shares a meal with his sister, Deborah, and Otis, revealing familial tensions as Otis embraces a gang lifestyle. An alarming drive-by shooting shatters the calm. The next morning, Davis finds solace in his hospital room, proclaiming, > "I have seen the light." Meanwhile, Claire views distressing images of poverty. An earthquake strikes, causing further chaos as Mack attempts to revive their elderly neighbor who suffers a heart attack.
That night, as tensions rise, Mack's dreams intertwine with Simon's presence, culminating with Claire's haunting visions of their son and the lost baby. The following day brings Davis's release from the hospital where Mack learns that Claire wishes to adopt the abandoned child. Despite Davis's hesitations, insisting he’s had a transformative vision, Mack ventures out with Simon for breakfast and offers to assist a woman named Jane in finding a more suitable home.
Davis shares his hospital experiences with Claire, expressing a desire to leave the film industry for something more meaningful. Claire updates him on their struggles regarding the adoption and the resulting marital tension. Mack tries to set up a date between Simon and Jane, revealing their connections. As the story unfolds, Jane and Simon embark on their first date while Dee uncovers more about Mack's life.
In the end, Deborah attempts a fresh start in a new neighborhood; however, Otis faces difficulties with the law, feeling that the backlash stems from racial discrimination. Dee resigns from her role, revealing her fleeting romance with Mack. Ultimately, the movie showcases the intertwining lives of these characters as they each move forward, culminating with Simon expressing his gratitude to Mack in a heartfelt farewell, leading everyone on a journey to the Grand Canyon.
