Stephen Hawking narrates his own story, from a Cambridge cosmology student diagnosed with motor neurone disease at 21 to the wheelchair-bound physicist whose synthesized voice became as recognizable as his theories. The film draws on interviews with Hawking himself, along with family, colleagues, and former students, plus home movies and archival footage that track his decline alongside his rise: the completion of his PhD, the writing of A Brief History of Time, his early marriage to Jane Wilde, and the years of ALS symptoms he outlived by decades. Rather than treating the illness as background tragedy, the film lets Hawking describe what it actually took to keep working, lecturing, and raising a family as his body failed and his fame grew. Colleagues place his black hole radiation work in context without turning the film into a physics lecture. The result is a portrait built from Hawking's own voice and memory rather than outside narration, following one man's account of becoming, as the title has it, a brief history of himself.