Annoying numerical name-spelling aside, Se7en has one of the most memorable finishes of the modern film era. It turns out that the gut-wrenching twist in David Fincher's 1995 classic only happened because of a weird mistake.
An interview with Se7en screenwriter Andrew Kevin Walker in The Hollywood Reporter offers up a mini-history of the film's development. Walker says that the infamous "what's in the box?" ending was part of his original draft of the project, but was removed in a later version after being optioned with director Jeremiah Chechik in mind. But when Fincher became involved, it was that original version that he wound up reading, Walker remembered:
[Fincher] expressed some interest, but in expressing his interest to them, had mentioned there was a head in the box. And they were like, 'Oh, no, no, no. We sent you the wrong draft.' And then they sent him the vastly rewritten, Jeremiah Chechik draft, which had a completely different ending and Fincher said, 'No, I wouldn't be interested in doing that.'
If Fincher's instincts hadn't gravitated to Walker's first crack at John Doe's story, then we would have gotten a much different — and possibly inferior — version of Se7en. Whoever it was that was plagued by the deadly sin of sloth, the world thanks you.