In late 19th century South Africa, an Indian lawyer confronts the harsh realities of racial discrimination after being forcibly removed from a whites-only train compartment. Shaken by this encounter, he begins a persistent, non-violent struggle for the rights of the Indian community living under the British Empire. His novel approach to activism entails civil disobedience and peaceful mass protests, which he leads with enduring patience and an unshakeable belief in non-violence. As his efforts yield some success in South Africa, he returns to his homeland of India, where he becomes a prominent figure advocating for independence from British rule.

Back in India, he evolves into a spiritual and political leader, spearheading the movement for Indian self-rule through non-violent means. Embracing a simple lifestyle and symbolically wearing the traditional homespun cotton, he connects with the diverse population of his country, from the poorest farmers to the urban laborers. He embarks on historic and challenging campaigns to alleviate poverty, expand women's rights, build religious and ethnic unity within India, and achieve the ultimate goal of Swaraj, or self-governance. His peaceful methods, charismatic leadership, and dedication to non-violence inspire millions to join in his quest, laying down the foundation for a nationwide series of resistances and demonstrations against the British colonial authorities.