The narrative begins with Laal Singh Chaddha, a gentle and kind-hearted Sikh man with a cognitive disability and leg braces, recounting his extraordinary life story to
strangers on a train journey to Delhi. As a child in 1970s Punjab, Laal is raised by a fiercely protective single mother who instills in him the belief that his condition does not define his worth. His life changes forever when he befriends Rupa D’Souza, a resilient girl with dreams of escaping her abusive home to become a glamorous Bollywood fashion model. Rupa is the only one who treats Laal as an equal, and a deep, lifelong bond is forged between them. During a childhood moment of distress, Laal’s leg braces magically shatter as he flees from bullies, revealing a phenomenal, and literal, running ability.Years later, while fleeing from college thugs, Laal inadvertently runs onto a football field, catches the eye of university scouts, and is propelled into a college football career despite his academic limitations. When anti-Sikh riots erupt in India following the assassination of Prime Minister Indira Gandhi, Laal’s mother sends him away to join the Indian Army to keep him safe. During his military service, Laal forms a profound friendship with a fellow soldier named Bala, whose ultimate dream is to start a lucrative underwear business. Tragically, the Kargil War breaks out, and Bala dies in Laal’s arms on the battlefield. Showing immense bravery, Laal runs back under heavy enemy fire to rescue wounded comrades, earning a gallantry medal from the President of India and national fame.Honoring his fallen friend, Laal teams up with a former Pakistani enemy soldier, Mohammed, whom he had also saved during the war, and together they launch "Bala Underwear," which unexpectedly transforms into a multi-million-dollar corporate empire. Despite his immense wealth and fame, Laal’s heart remains tethered to Rupa, who is now entangled in a
toxic relationship with a corrupt, violent Mumbai businessman. When Rupa’s boyfriend is arrested for murder, she flees to Laal’s estate, seeking solace. Grateful and overwhelmed, Rupa temporarily returns Laal’s romantic feelings, but her deep-seated insecurities about her past and unworthiness cause her to abruptly abandon him once again to pursue her ambitions in foreign lands.Devastated and heartbroken, Laal embarks on an epic, spontaneous four-year cross-country running marathon across India, capturing the media’s imagination and inspiring a disillusioned nation. Eventually, he stops running and returns home, receiving a letter from Rupa that reveals she is dying from a terminal illness and has given birth to his son, Rohit. Laal rushes to her side, where they finally achieve peace and shared parenthood before Rupa passes away. The film concludes with the adult Laal happily raising young Rohit, ensuring the boy knows love, kindness, and the enduring legacy of his mother.