“I did not kill my wife!” exclaims Ben Affleck in the first official trailer for David Fincher’s Gone Girl. “I am not a murderer.” Problem is, the trailer looks like a fan-made video, and could well be the worst thing we’ve seen this year. What’s going on?

Gone Girl

Affleck stars as Nick Dunne in the movie. He’s an ostensibly nice guy – a workaday husband looking forwarding to building a family. The American dream. But, coming home on day, he discovers his wife, Amy Dunne (played by Rosamund Pike), is missing. 

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Amy’s diaries present a much darker picture of her husband, turning him into their prime suspect and forcing Dunne into denying that he killed his own wife. The psychological mystery-thriller is directed by Fincher, who also directed The Social Network, The Girl With The Dragon Tattoo and the Netflix series, House Of Cards.

That’s all well and good; but why, then, did they go and make this weird trailer? And why is every other site talking about it like it’s a perfectly normal thing? Richard Butler’s eerie cover of the Charles Aznavour’s song “She” runs nearly for the duration, and the crescendo towards the middle is akin to a low-level media project undertaken by an uninterested kid. 

Gillian Flynn's popular book – upon which the film is based - was published in June 2012 and by the end of its first year on the shelves it had sold over two million copies in print and digital editions. But the ending was controversial, and Flynn set about rewriting it for the film, insisting she performed major surgery in upheaving the story’s climax. 

Ben AffleckBen Affleck insists he's innocent in Fincher's 'Gone Girl', which has a brand new ending for the cinema

“Ben was so shocked by it,” Flynn told EW. “He would say, ‘This is a whole new third act! She literally threw that third act out and started from scratch.’” She added that “there was something thrilling about taking this piece of work that I’d spent about two years painstakingly putting together with all its eight million Lego pieces and take a hammer to it and bash it apart and reassemble it into a movie."