Book for someone going through major life changes (more details inside)

My dad is about to go through some major life changes. He’s not a reader but I’ve managed to gift him books he ended up liking, and it’s become somewhat of a tradition. This time I’m looking for books about facing big changes, especially when you’re getting oldish/retiring and have been very successful in your career.

Examples of authors he likes:
– Ken Follett when he writes about more recent times
– Richard Matheson
– Georges Simenon when he’s autobiographical
– Charles Darwin

What I’m looking for:
– fiction or autobiographies
– short, self-conclusive books
– concurrent themes beyond change: the sea, thrillers, spies, animals (surviving), self-reflection (not too much).

He’s not really into classics or self-help books.

Any ideas? Thank you!