The film opens in 1951 in a quaint village named Idar within the Sabarkantha district of northern Gujarat. We meet Gurukant Desai (Abhishek Bachchan), a young man fueled by aspirations of success. He struggles against the pessimism of his father, Kantilal (Rajendra Gupta), the local school headmaster, who warns him that "dreams never come true." After failing his school exams, Guru feels the pressure to find a job and contemplates a new direction in life.
Determined to change his fate, Guru embarks on a journey to Turkey, where he becomes involved in the spice trade and later works for Burmah Shell. Although he receives a promotion, the notion of working for someone else doesn't sit well with him. His mentor, Ghanshyam Das (Manoj Joshi), feels a sense of loss as Guru prepares to return home.
Upon his return to Idar, Guru is resolute in his desire to start a business. With 15,000 as seed money, he seeks an additional 15,000 from his friend Jignesh (Arya Babbar), but Jignesh reveals that his father, Kaka (Sachin Khedekar), won't invest, having set aside funds for his daughter's wedding. In a strategic personal move, Guru marries Sujata (Aishwarya Rai Bachchan) for her dowry. The trio—Guru, Sujata, and Jignesh—then relocate to Bombay, where Guru aims to dive into the cloth trading business.
However, upon entering the market, Guru soon learns there are gates to success controlled by Arzan Contractor (Arjan Bajwa), the president of the traders' association. Meeting Arzan, Guru believes he can secure entry, yet, his application gets rejected months later. Frustrated and determined, he encounters Manik Dasgupta (Mithun Chakraborty), a newspaper publisher living in close proximity to Arzan. Supported by Mathura Das (Sudhir Pandey), Manik publishes a revealing article that sheds light on Arzan's monopolistic grip on the traders' union, prompting Arzan's resignation. Grabbing the opportunity, Guru finally secures his trading permit and opens his office.
Guru has a swift rise, trading in polyester during a time when the market is dominated by cotton. Arzan attempts to thwart him by claiming the market is gambling and urging IAS officer KR Menon (Prathap K. Pothan) to enforce a lock. In a bold move, Guru confronts Menon, threatening to reveal all of his raw materials, which forces Menon to conform to public demand. As time passes, Guru's venture blossoms into the Shakti Corporation, earning him the affection of Manik, who becomes a father figure to Guru, and a friendship with Meenu (Vidya Balan), Manik's granddaughter. However, Meenu's journey is marred by illness, as she develops multiple sclerosis.
Seeking to expand further, Guru contemplates an IPO for Shakti Corporation, leading to discontent for Jignesh, who feels excluded. Tensions rise when Jignesh criticizes Guru’s intentions toward Sujata, claiming he only married her for her dowry. Following a period of separation, Guru wins Sujata back, and they reconcile as he constructs the factory with the help of Ghanshyam.
In just a few years, Guru amasses an empire that draws the attention of Arzan's father (Dhritiman Chatterjee), who attempts to purchase the company. Guru stands his ground, exposing the Contractor family’s corruption in every newspaper possible. However, as his empire grows, so does the shadow of his illegal actions—manipulating markets and evading duties—eventually catching up with him. Nanaji learns of Guru's corrupt methods and, along with reporter Shyam Saxena (Madhavan), decides to hold him accountable. The situation worsens as Sujata gives birth to twins, while Meenu suffers from her illness.
When Shyam publishes an exposé on Guru's illegal dealings, despair leads Ghanshyam to attempt suicide, and Guru finds his stakeholders turning against him, branding him a smuggler. The mounting pressure triggers a debilitating stroke that paralyzes him.
As tragedy strikes both the personal and professional realms, the film climaxes with Guru facing a government inquiry on October 16, 1980. In this pivotal moment, he describes himself as merely a villager whose ambitions were curtailed by a corrupt system that forced him into dishonest practices. Remarkably, this narrative prompts the government to drop most charges, and Guru emerges with a fine, allowing him to reclaim his position.
The tale concludes with Guru addressing Shakti's shareholders, reflecting on how he proved his father's skepticism of dreams wrong. He ignites a spirit of perseverance among them by questioning if they should stop now, met by a resounding refusal. They resolve to strive toward becoming the largest company in the world.
