Complex sentence: Renwick decided to use the flashback structure because he realised that most viewers would have been aware of Victor's death because of the press coverage; there would be little point in a climax in which everyone already knew the outcome.
Split into simpler sentences: Renwick decided to use the flashback structure because he realised that most viewers would have been aware of Victor's death through the press. There would be little point in a climax in which everyone already knew the outcome.