Albert Einstein's theory of general relativity has revolutionised our understanding of gravity, space and time. Initially acclaimed, then forgotten, and now rediscovered, the adventure of this hundred-year-old theory has marked the scientific history of the 20th century. From its inception, a mathematical difficulty arose that could have nipped the theory in the bud: the Schwarzschild singularity. In the company of great international relativistic physicists, the viewer embarks on a discovery of this theory with a singular destiny. We discover a "curved" universe that proves to be even stranger than Einstein had envisioned, and harbours some objects - such as black holes - that still challenge today's scientists.