Movie characters who completely changed over a franchise

For better or worse, who are some movie characters who completely changed over the course of a franchise?

If you compared the character in the first/earliest film(s) with how they are in the latest/last film(s), it would be like seeing two different characters even though they're supposed to be the same character.

For example:

John McClane - Die Hard
Martin Riggs - Lethal Weapon
Luke Skywalker - Star Wars