Provenance of Shadows
Provenance of Shadows is a Pocket TOS novel – the first novel in the Crucible trilogy – written by David R. George III. Published by Pocket Books, it was first released in .

Summary 
From the book jacket
IN A SINGLE MOMENT…the lives of three men will be forever changed. In that split second, defined paradoxically by both salvation and loss, they will destroy the world and then restore it. Much had come before, and much would come after, but nothing would color their lives more than that one, isolated instant on the edge of forever.

IN A SINGLE MOMENT…Leonard McCoy, displaced in time, saves a woman from dying in a traffic accident, and in so doing alters Earth's history. Stranded in the past, he struggles to find a way back to his own century. But living an existence he was not meant to, he will eventually have to move on, and ultimately face the shadows born of his lost life.

IN A SINGLE MOMENT…Leonard McCoy, displaced in time, is prevented from saving a woman from dying in a traffic accident, allowing Earth's history to remain unchanged. Returning to the present, he encounters a medical mystery he is committed to solving. But the echoes of an existence he never lived haunt him, and the specter of a premature death will bring him full circle to the shadows he has never faced. Background information 
 In developing the concept for this novel, author David R. George III ended up conceiving the nature of the trilogy as a whole. In rewatching  episodes as preparation, he "began to notice an aspect of Dr. McCoy's life not generally discussed, less an intentional creation by the writers, I suspected, than simply an unintentional artifact of the collection of stories they'd told"; namely, that McCoy "had lived as something of a loner, at least in terms of romance. [… All] of that led me to a question for which I wanted to find an answer: Why did Dr. McCoy have so little love in his life?" He was able to combine that discovery with a realization that part of McCoy's timeline had not previously been explored – the alternate life he must have spent on 20th century Earth after he stepped through the Guardian of Forever in  – to come up with the story for Provenance of Shadows. In connecting with City, George realized that those events would have profound effects not only on McCoy, but Spock and Kirk as well, which led him to develop the entire concept of Crucible and the idea of the novels focusing on each of the three characters individually. (; The Star to Every Wandering afterword)
 An extract from this novel appeared in .

 Characters 
Tonia Barrows
Bates
Christine Chapel
Pavel Chekov
DeSalle
Hadley
Edith Keeler
James T. Kirk
Peter Kirk
Korax
Leslie
Joseph M'Benga
Joanna McCoy
Leonard McCoy
Natira
Nogura
Palmer
Rahda
Benny Russell
Montgomery Scott
Spock
Hikaru Sulu
Nyota Uhura
Zahra
Zarabeth

 References 
; Carrington Award; chroniton; Comparative Alien Physiology; Data; ; ; ; ; Fabrini; Guardian of Forever; Nexus; World War II; Vegan choriomeningitis; xenopolycythemia; Yonada''; Zee-Magnees Prize

External link 
 

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Novels
Scribe Award nominees