The end of the climax, where the sound fades into a terrible song, my mouth was agape. Could not believe the lazy filmmaking I was witnessing.
This review may contain spoilers. I can handle the truth.
Overall, a great theater experience (as most Fincher films are), but definitely had some issues in the third act:
1) There's no way I could go along with Nick & Amy staying together in the same house after she returns.
2) I loved the scene where the lady cop was with the Feds and was trying to ask questions. But after that scene, she's like "Sorry, it's out of my hands." If you knew a story like Nick & Amy's, you wouldn't just fold over.
3) Not the Chasing Amy sequel I imagined.