I'd been sent to the gates of Leavesden Studios in Hertfordshire to check out the chaotic, buzzing festival of awesome wizards and magical mayhem.
Well, that was the idea.
But, as you can see from the pix, the first day of filming was a pretty quiet affair from where I was standing.
Mysterious black windows
Loads of cars went in and out, some with mysterious blacked out windows - who was inside?
There were tons of vans and lorries carrying hundreds of planks of wood, strange looking canisters of gas and food for the cast and crew.
But nothing which gave anything away.
If there was any filming happening, it was well away from public view, in one of the huge sound stages which hold loads of the sets.