One of the stories in Clockwork Lives is "The Percussor's Tale," about a music professor in declining health who creates a steam-driven mechanical drummer with perfect rhythm. At the end of the story, the Percussor performs an incredibly complex symphony for the Watchmaker. This grand symphony was a tour of the wonders of the world, including "the legendary lands of the far north, Ultima Thule -- a mirage of tremendous glaciers under dark skies that danced with shifting veils of colored light." After writing that passage, Neil remarked that it would be fun to visit the far-flung icy landscape of the great white north under the auroras . and we realized that the Northern Lights must be the source of the quintessence. I suggested that we could take old Owen Hardy out for one last adventure, this time with his bright-eyed young grandson Alain. It quickly became apparent that they must be on a mission for the Watchmaker, who was running down after centuries of his Stability, and he needed Owen and the boy to find him a new source of quintessence. And if we were going to set the adventure up in the vast frozen wastelands, then another famous Rush reference would have to make an appearance: "By-Tor and the Snow Dog.

" Instantly, the backbone of Clockwork Destiny was formed. For a couple of years, we dabbled with the idea off and on, and I kept notes of our conversations and other plot possibilities. I would talk with Neil about the story whenever we got together, but I had other book projects and deadlines. Neil embarked on the all-consuming R40 Tour, Rush's last tour, which required extensive practice and rehearsals, and then months on the road before their final show in Inglewood CA on August 1, 2015. Previously, Neil and I had taken a three-year break between the publication of Clockwork Angels and Clockwork Lives, and we had no contract for Clockwork Destiny, no deadline. We decided to let it develop organically, since these novels were extremely special to both of us. There was no hurry. We had all the time in the world.

Until we didn't. Not long after he retired, Neil was diagnosed with glioblastoma, a form of terminal brain cancer. From that point, whenever we did meet or talk, we would dabble a little with Clockwork Destiny , but there were other things to occupy our conversations. The import of this novel, with its underlying theme of death and legacy and paying it forward, did not escape us, and writing it took on an entirely different perspective for me. An impossible task. We both knew that it wouldn't be finished until after he was gone. Time is the true anarchist.