 Complete the following phrase:  The film portrays the increasingly complex dynamics and tumult that characterized Sennas years as world champion, his battle to improve his sports safety, and his reactions as he witnesses accidents and eventually the death of Austrian fellow-driver Roland Ratzenberger the day before his own. We see and hear through Sennas point of view that innovative computerization led in these years to the technological domination of the Williams cars, with Prost joining Williams and, in a fallout with Senna, refusing to be on a team with Senna anymore. The documentary reaches its finale as Prost retires and Senna takes up a champion driver spot with Williams, the Grove-based team in 1994, just as Formula One rules change, disallowing computerization, and the Williams cars undergo rapid reconfiguration that proves fatal. In the culminating weekend of his life, at that years San Marino Grand Prix, footage shows Senna under extreme stress, troubled as safety conditions reveal their weaknesses in one track accident after another over three consecutive days. Rubens Barrichello is injured in a crash during Friday qualifying, Ratzenberger is killed in an accident during final qualifying on 30 April, and at the start of the race JJ Lehto stalls and is hit at high speed by Pedro Lamy. The safety car is brought out, and when racing resumes, Senna 