Character Derailment/Film


 * Dr. Lawrence Gordon's long-awaited return in Saw 3D may count as this. This is considering the last time we saw him (in part 1), Lawrence was crawling away from his bathroom-prison, shivering from the blood-loss incurred from cutting off his foot and promising he'd find help for the still-shackled guy being tested with him (this is after he believes his family may well have been shot and killed due to his inaction in the "test").
 * An even better example is Jigsaw himself. Jigsaw made a huge point that he never killed anyone, merely put them in position where they had to fight and occasionally compete to live. Then in Saw VI he suddenly was fine with using Hoffman's traps, which did kill people outright.
 * Purposely done in the case of Susan Orleans in Adaptation. Portrayed as simply a reporter who develops a bond with John Laroche, due to Charlie Kaufman's in-story Creator Breakdown she proceeds to become a psychotic drug-addict who regrets her entire life.
 * In The Neverending Story, The Rock Biter is a mostly serious character, who has some tragic moments ("They seem like big, strong hands, didn't they?"). In the sequel, they give him a child. In the third, Rockbiter (now even referred as "Rockmuncher" at one point) is a doofus wearing a rock wifebeater, with sitcom-like scenes with his full family, and having a terrible, off-key musical number.