Venus and Serena

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Sisters Venus and Serena Williams are two of the most successful tennis players of all time, winning championships for over a decade and pushing the limits of longevity in such a demanding sport.

Following their extraordinary story, this film features unprecedented access into their lives during the most intimidating year of their careers.

Over the course of 2011, Venus grappled with an energy-sapping autoimmune disease, while Serena battled back from a life-threatening pulmonary embolism.

Available to UK users only

BBC Sport