Character interviews - how to handle characters that age noticeably within a single novel

Question

Many writers employ an interviewing technique in order to give characters depth and realism within a plot. This makes sense to me and is a solid practice for creating deep, meaningful characters that foster realistic relationships within the prose.

My question is regarding characters who age noticeably throughout the course of a single novel. My specific example is a protagonist who is 25 years old in the first act, and after a gap which is not directly portrayed, is 46 in the second act. To add to this, there is also a potentially life changing event planned for the first act.

Should I interview this character as a 20 year old, a 40 year old, or at both ages, as separate interviews?

Answer 1

Both ages as separate interviews, since his answers will be different and you will have to handle his responses differently. In the second interview, he can even look back and say "Yeah, I remember the first time you asked me this. I can't believe I said X! Now I know thus-and-such and it's definitely Y."

Answer 2

Although I like the concept of character interviews, in this special case, I would sketch the entire character's biography. In that way you not only have a clear idea of the character's personality state at the two times of your story, but you will also have a keen sense of the character's development in-between (think Boyhood here). It's more work, but for me, it pays off in the end.

If you want to stick with the interviews, I would definitely do the extra work and write both interviews.