When I was 30 or so - by that time I had become an assistant D.A. - I decided I would try to write a novel. To be clear: I did not decide to become a novelist. Honestly, it never crossed my mind that I could actually earn a living as a professional novelist.
We went into darkness after being in daylight the whole time on the way to the Moon. And then we went into darkness. And we're in the shadow... of the Moon.
The key to this collaboration - which we undertook after much deliberation - was to stretch creatively. New characters, new locales, new form (the novella).

