Chapters 0 and 1 in this book by Mattuck are also a fantastic read for a general audience interested in what's going on 'under the hood'. https://www.amazon.co.uk/Feynman-Diagrams-Many-body-Problem-...

Feynman's own book 'QED: the strange theory of light and matter' is another good read, but strangely it is a bit lacking in illustrations. (And the illustrations that are there are a bit dry compared to Mattuck!)