As a movie by itself?
2 stars. Incoherent plot, very wooden acting, characters were boring, worldbuilding somehow about as interesting as paint drying, character motivation thrown everywhere to justify a rushed plot. CGI I thought was really well done and a couple set-pieces were decent to watch.
If I took into context being a book fan, this would get one star. Interesting character arcs thrown away in favour of B-movie tropes and generic plotlines, movie somehow makes Artemis a criminal mastermind despite him not doing anything really criminal and barely a genius at all. The books not only far more convincing but also had a better plot.
This is not film snobbery. This is a bad movie. This is a bad kid's movie, too, unless your definition of "good kid's movie" is a rush of colours and weird-looking characters with some random wide-eyed kid in the middle.
I wish they'd come up with their own original fairy world to stuff this plot and characters in. Would've been much more convincing as a straightforward action-comedy starring fairies and an Irish kid.
Attempting to shade this movie with a couple darker undertones and combine various plot points spread across the books, along with the most idiotic character arc (hero to villain) ever put to screen turns what could've been a generically fun 3 star romp into a 2 star movie close to a garbage fire.
Bad. Like I said. As a book fan 1 star. But on it's own merits the movie is vaguely enjoyable enough to warrant 2 stars. Make no mistake this is not good. Hope they never make a sequel and reboot this with a better screenplay in 10 years.