Lucy is not bad. Lucy is a struggling drop-out in Taipei, who is dragged unwillingly by her new boyfriend into a drug deal gone wrong, used as a drug mule, accidentally ingests a fictional drug which unlocks human potential, acquires lots of psychic powers, and begins transcending humanity into... something.
The first bit, with Taipei drug gangs who don't speak English, is quite effectively scary.
As long as you manage (with GREAT difficulty) to ignore the "only use 10% of our brains" premise, the science is internally fairly consistent.
It's comparatively male-gaze-free, and just passes the Bechdel test (though maybe could have done better).
It paints a good picture of becoming superhuman. OTOH, I was left feeling a bit "...and? so?"
And a few things bugged me. Do international drug gangs really storm French universities in the teeth of a machine-gun battle with interpol? Like, I know I tend to over-estimate how much civil order is the norm, but that seems a bit... blatant? I thought drug gangs, even big ones, tended to try to keep things deniable, to get expendable minions to take the rap and keep going, not take on governments head on. Like, sure, you appear to be able to outgun the first twenty or so police who turn up, but France has tanks.
It wasn't unrealistic, but I was amused by "she won't give up" -- no, you haven't really established whether she'd give up if she had any reason to give up, you've just established she's immune to bullets.
I get, part of becoming superhuman may be caring less about individual human lives (whether or not I agree). But "flipping three policecars into a crowded street market" just seems gratuitously carnage-ful. What was wrong with plan A, "have your policeman friend ask them nicely to stop"? Or plan B "let them follow you to the drug-gang-shootout where they'd be quite handy"? Or plan C, "just ignore them?" Or plan D, "use psychic powers to make them just roll gently to a stop?"