The best Star Trek novels that are sequels to original series TV episodes

I love a great Spock story, especially when his struggle between logic and emotion is at the forefront. That struggle is externalized and emphasized in this book when he discovers he has an adult son who has not been raised as a Vulcan. The tension between father and son plays off Spock’s troubled relationship with his own father.

It came out just a year after Star Trek II, four years prior to The Next Generation, so I eagerly awaited each book for my Trek fix, especially when they played off an episode because it was often a challenge to see the old shows in the eighties. In the episode “All Our Yesterdays,” Spock, stranded in the distant past, had reverted to a pre-logic Vulcan and fallen in love, providing Crispin with her setup; she eventually wrote a follow-up, Time for Yesterday.

The standout hook for me is the presence of Roberta Lincoln from the episode, "Assignment: Earth"; I wish the inimitable Terri Garr had reprised the role in an episode of The Next Generation, where she could have demonstrated the same growth of character from clueless receptionist to temporal secret agent that’s on display in this action-packed novel.

Time travel has often resulted in some of my favorite Trek stories, and From History’s Shadow dives deep into the many temporal twists and turns the franchise has introduced over the decades. There’s also a healthy helping of the space race, alien invasions, and flying saucer coverups, all very much in my geeky wheelhouse. And I love period settings—here we get scenes spread across the 1950s and 1960s in addition to being on the Enterprise during Kirk’s classic five-year mission.

One of my favorite “But what happened after that?” moments of the original series was the challenge Kirk issued the goateed Spock at the end of "Mirror, Mirror": What will it be? Past or future? Tyranny or freedom? It's up to you. David Mack weaves a three-decade-long epic that answers the questions—with shades of the psychohistory of Asimov’s classic Foundation trilogy—as Spock plays a three-dimensional chess game of moves and countermoves to bring about the downfall of an empire.

The Sorrows of Empire has everything I want from a Mirror Universe story: revolutionary intrigue, imperial treachery, and a cast of interesting mirror versions of characters we know and often love from the “true” universe. It also deftly incorporates the increasingly complicated canon of the Mirror Universe introduced by the other series over the years.

A novel from Greg Cox is always going to bring me the kind of deep-cut Trek continuity I love, but Foul Deeds Will Rise goes above and beyond by bringing me the sequel I didn’t know I needed: the return of Lenore Karidian, last seen twenty years earlier suffering a psychotic break after accidentally killing her mass-murderer father in the episode “The Conscience of the King.”

I also love when Trek plays in other genres, and here we get a murder mystery: Kirk has to investigate whether Lenore was successfully rehabilitated after serving her time for psychiatric treatment, or if has she fallen off the wagon and gone on a killing spree that could derail an entire peace process. Beyond the immediate plot, it plays amusingly well off Kirk’s long history of getting involved in doomed relationships. 

I always wanted to know what happened after the episode "The Corbomite Maneuver," which ended with a young crew member sent off to the mysterious First Federation—never to be heard from again in the shows. I always enjoy Christopher L. Bennett’s meticulous sci-fi world-building, and in his hands, the First Federation is revealed to be a suitably fascinating, if isolated, society.

I loved the sense of vastness achieved by getting beyond the United Federation of Planets. I also enjoy when a story takes full advantage of the continuity of the franchise, and The Face of the Unknown smoothly sets up elements of the often overlooked Animated Series of the 1970s as well as Star Trek: The Motion Picture.