Charlotte started interesting. Highschool kids suddenly getting super powers, but all of them having some kind of negative condition to them.
With our main character going all "Lelouch" with his power of going into someone else's body and controlling them, but its only for 5 seconds.
It turns into a fun romp with his new student council friends (when the student council leader girl blackmails him to help them, after recording him using his powers). Meeting other teens with super powers, and saving them from evil organizations.
It then does some crazy turns in the plot that could have just as easily been their own story (spoilers):
- a whole other storyline about his unknown big brother going back in time repeatedly to save them from their original fate of all becoming lab rats. Finally creating the school we've seen through the show, they use for hiding the super-powered teens. But losing a little of his eyesight every time he uses his powers, he eventually loses his power and becomes blind.
- main character's little sister dying. Finding out from his big brother, his power actually steals other user's powers in the short period he controls them. So he steals his bro's power of time travel to save their sister.
- Getting one eye blind after an evil organization takes his student council girl hostage. Understanding that these powers are too dangerous to exist, he attempts the near-impossible task of steal the powers of everyone in the world. With the student council leader girl giving him a set of reminder notes of basic words he could use overseas.
From the strain of these tens of thousands of powers he steals, he begins to lose himself. Unable to sleep from heightened senses, getting serious amnesia, becoming insane, and even questioning 'with all these powers why not just become god and rule over everything to create peace?'.
The reminder notes makes him remember his task though, even though he's forgotten every person and place he knew. It helps him continue along.
It has a sweet ending, with his big bro and his student council friends finding him, after he completes his task stealing the last user's power in China.
He goes through a lot, and loses his memory, but eventually saves everyone he can without falling to his powers.
The middle of the show gets pretty weak. But that last episode was some seriously emotional stuff.