Terrible movie. First of all, the characters are stupid. Thomas should've come with WICKED when they came to pick him up in the 2nd movie. They could've found a cure way faster and less people would've died. Second, Teresa kind of went stupid at the last part of the movie. She was the only living doctor left (at least, in the movie) who knows how to convert Thomas's blood into a cure but did a useless sacrifice instead. And then there's this Janson guy who kept shooting random people for absolutely no reason. And then the people outside the city. The doctors are only trying to find a cure, yet they chose to be stupid and bombed the entire facility. Now all of them are doomed to the Flare because they killed every last doctor who could've been able to help them. Third, they didn't explain what made Thomas's blood a cure.
But ig this movie wouldn't have existed if it always went right.