The Spiderwick Chronicles
Scared the shit out of me when I first watched it in 2008. How can it possibly be 6+???
But honestly such a banger. Looking back now I remember drawing my own fairy creatures and imagining how invisible elfs and fairies live in the flowers. Worldbuilding 10/10.
P.S. now Im going to rewatch Artur and the Invisibles to completely heal my inner child.