My Letter box log of Se7en (Spoilers):

Maybe this is an obvious detail, but I hadn’t noticed before. For the entire film, detectives Summerset and Mills sludge through damp darkness searching for the truth. It’s not until the third and final act that we ever see the sun. And in that last minute, the truth is revealed in a dark and damp box.

I also noticed how Fincher used themes of beginnings and endings as a sort of misdirect. I don’t recall how I thought Seven would end when I first saw the movie, but if I had to guess, I’d say it was Summerset who’d be killed—the old detective days from retiring. What made the ending so stunning, other than the obvious, was that it was the new detective with the new wife and child who fell victim to John Doe.