David Fincher reportedly requested new ending following poor returns for faithful adaptation of The Girl with the Dragon Tattoo

The dramatic finale to bestselling Gillian Flynn psychological thriller Gone Girl has been completely rewritten for the highly anticipated upcoming film adaptation by acclaimed director David Fincher, according to Entertainment Weekly.

Flynn has written a new third act for the movie, Fincher's follow-up to his reworking of another literary sensation, Stieg Larsson's The Girl with the Dragon Tattoo. The suggestion is that Fincher asked for the change after realising he had held too close to the source material for the 2011 film, which was something of a box office disappointment, despite strong reviews.

Gone Girl stars Ben Affleck opposite Britain's Rosamund Pike as a couple, Nick and Amy Dunne, who quit New York for the midwest after Nick loses his job. The pair open a bar but strains emerge in the marriage, and Amy suddenly goes missing on their fifth wedding anniversary with Nick finding himself the main police suspect.

"Ben was so shocked by it," Flynn said of the screenplay. "He would say, 'This is a whole new third act! She literally threw that third act out and started from scratch.'"

Nevertheless, the writer said she enjoyed pulling apart her own creation and reassembling it in a form befitting the big screen. "There was something thrilling about taking this piece of work that I'd spent about two years painstakingly putting together, with all its 8m Lego pieces, and take a hammer to it and bash it apart and reassemble it into a movie," she said.

Gone Girl is due in UK and US cinemas on 3 October.