I'm brand new here, and I hope I'm not breaking any protocol by my first post being a question.

I'm writing a screenplay wherein the main character's name changes maybe 10-15 pages in; think Genghis Khan, who was really named Temujin for much of his life, or Geronimo, who was named that after a particular battle.

Also similar to those examples, we meet the character when he is a child, and around 12 years old, he gets a new name. So - what is the appropriate way to handle that? It seems odd to call him by his new name when everyone else is calling him by his "original name."

Any thoughts?