Original sentence: The  documentary begins with  Tyson's convincing championship win over Berbick, then begins to explore the fighter's upbringing and motivation.Tyson is a 2008 documentary film about the life of former undisputed heavy weight champion of the world boxer Mike Tyson
Edited sentence: The documentary begins with Tyson's convincing championship win over Berbick, then begins to explore the fighter's upbringing and motivation.Tyson is a  documentary film about the life of former undisputed heavy weight champion of the world boxer Mike Tyson