Q: In what key is the main Harry Potter theme by John Williams? Has a lot of notes right next to each otherthere's even that part that's like nanananananaNANAnaNANANANA that's 3 notes right next to each other
A: i have never heard it but after listening to this version:
https://www.youtube.com/watch?v=Pf-8WMI-7J4 (the first version i found), for at least the first 40 seconds, despite a bit of adventurousness, E minor is unquestionably the home key for at least that far