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Time in the galaxy has stopped running in its normal course. That can mean only one thing—the Guardian of Forever is malfunctioning. To save the universe, Starfleet Command reunites three of its most legendary figures—Admiral James T. Kirk, Spock of Vulcan, and Dr. Leonard McCoy—and sends them on a desperate mission to contact the Guardian, a journey that ultimately takes them 5,000 years into the past. They must find Spock's son Zar once again, and bring him back to their time to telepathically communicate with the Guardian.

But Zar is enmeshed in troubles of his own, and soon Kirk, Spock, and McCoy find themselves in a desperate struggle to save both his and their world.

303 pages, Paperback

First published May 1, 1986

About the author

A.C. Crispin

64 books308 followers
Ann Carol Crispin (1950-2013) was an American science fiction writer, the author of over twenty published novels. She wrote professionally since 1983. She wrote several Star Trek and Star Wars novels, and created her own original science fiction series called Starbridge.

Crispin also served as Eastern Regional Director, and then Vice President, of the Science Fiction and Fantasy Writers of America. With Victoria Strauss, she founded Writer Beware, a "watchdog" group that is part of SFWA that warns aspiring writers about the dangers of scam agents, editors, and publishers. Writer Beware was founded in 1998, and has assisted law enforcement and civil authorities in tracking and shutting down writing scams.

Crispin, who also wrote a prequel providing the back story for the popular Pirates of the Caribbean movie series, died on September 6th, 2013 at the Hospice of Charles County in Waldorf, aged 63.

She was married to science fiction author Michael Capobianco.

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5 stars
694 (36%)
4 stars
686 (36%)
3 stars
439 (23%)
2 stars
70 (3%)
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8 (<1%)
Displaying 1 - 30 of 83 reviews
Profile Image for Matt.
686 reviews
April 13, 2016
On it's own Time for Yesterday by A.C. Crispin is a decent, fun Star Trek novel whether one has read it's precursor novel Yesterday's Son. With that said, one's enjoyment of the novel and understanding of the interactions between Kirk, Spock, and McCoy (as well as the majority of the TOS Enterprise crew) with Zar can only come after having read Yesterday's Son. The book contains two plots that cross with one another thanks to time travel, but it's the initial one of the malfunctioning Guardian of Forever that comes across as the better of the two especially as the reader meets the creators of the Guardian.

Having been given this book by a relative, I didn't know what to expect. The book was a fun read, but after the Guardian plot was wrapped up the rest of the book was missing the backstory that Yesterday's Son would have provided. So you're thinking about reading this book without having read Yesterday's Son, I recommend you don't. Find Yesterday's Son either on Kindle or at a used book store or at a friend's house and read it first before Time for Yesterday. I fully intend to find Yesterday's Son so I can re-read this book and have a better appreciation (and review of it).
Profile Image for Clint Hall.
181 reviews14 followers
February 1, 2021
My review of 'Yesterday's Son' was something along the lines of 'Read like an episode, albeit a forgettable one'. 'Time for Yesterday' read like a Star Trek movie . . . albeit a forgettable one.

It started out well enough, with lots of space action and a galaxy-shattering enigma. I wanted to like it, in fact, I thought I would be writing a praising review about it. But then the story turns into a sword-and-sandal epic. Which would've been fine if the story started out that way. It just felt like it was going in too many different directions and the main focus of the story was thrown out at about three quarters in favour of another story.

There were some interesting additions to the mythos that the author created (or added upon), but this was another forgettable Star Trek novel.
Profile Image for Therese.
Author 3 books274 followers
January 7, 2021
Mr. Spock was my first ever pre-sexual, sexual crush. This book, stolen from my mom's box of star trek books in the 80s, proved he'd had sex. In a cave! With a time-stuck cave lady. Cuz he went all primal. Yeah. And then a son, even more human than he was.

This is all. I can not and will not explain my five star rating otherwise except to note that five star ratings are for the occasional flawless book, or the book that stuck the reader very specifically.

Spock + 12yr Old Therese 4EVAH!!!
This entire review has been hidden because of spoilers.
Profile Image for Jamie.
1,294 reviews168 followers
July 12, 2019
Spock focused story that ties into the TOS episode All Our Yesterdays and the author's previously published story Yesterday's Son.
Profile Image for Reesha.
202 reviews5 followers
September 26, 2022
I quite enjoyed this one. The danger to the universe was intriguing, the Guardian of Forever is always nice to see again, Sarpeidon's expanded history was engaging, and the Originators were fascinating. (In fact, I'd like to see a more fleshed out story of the Originators now, especially one exploring the theory that they were also the Progenitors and the Preservers.)

I liked Zar from the first book, wanting a follow-up on him before I'd known there was one, and his story in this book didn't disappoint - despite admittedly being a bit unbelievable and even slipping into "Mary Stu" territory at times.

I was also fond of several of the other original characters, especially Wynn. Now I'd like to see more about her! But, alas, though originally more were planned, I do believe this is the last in the series.

Uhura has a small roll in this book, but I still enjoyed her scenes. She demonstrates quite clearly that there is a difference between being an esper (empath) and actually being empathetic, managing to save precious young lives in the meantime. That said, it was a strange wrap-up to another original character who seemed they would be much more important at the beginning of the book than they ended up being, as if the storyline just faded away in the author's mind when others became more interesting to write.

I also enjoyed how the conversations among Kirk, Spock, and McCoy fit neatly between the first and second Star Trek movies. It made things feel more seamless than they often do in the early novels.

I wouldn't mind reading this series again, both books back-to-back this time, instead of more than a year apart as I read them this time (I'm reading all books in publication date order; book #1 was written in 1983, book #2 in 1988, with nearly 40 other novels between them).

I'm sad to say goodbye to Zar. But I can definitely recommend this series of two to Trekkies. Just make sure to read them in order!
833 reviews36 followers
October 9, 2016
I liked this one better than "Yesterday's Son." Crispin fleshes out her original character, Zar, as well as the culture he is working within, which I liked.
Profile Image for Graff Fuller.
1,611 reviews26 followers
February 19, 2024
Time for Yesterday by A.C. Crispin

Adventurous, challenging, funny, hopeful,
informative, inspiring, mysterious, reflective, sad, and tense.

Medium paced

Plot- or character-driven? A mix
Strong character development? Yes
Loveable characters? Yes
Diverse cast of characters? Yes
Flaws of characters a main focus? Yes

4.5 Stars

This author is a fan. You can tell how she dedicated this story...and the love and care that she infused INTO the story.

This is technically a Part II, though in true Star Trek novel fashion, you really don't need the previous story...though there's MORE depth to the story, IF you have read it.

Zar is Spock's son. He is living on a planet in another time period. The Guardian of Forever transported him there...and he is trying to save this planet.

Unfortunately, the people of OUR time, with the Federation and the crew of the Enterprise...NEED him, too.

So, Spock, Admiral Kirk and Bones and the crew decide to find a way to bring Zar back to our time period...to save the planets/suns from dying prematurely. 

If this sound remotely interesting (the failure is mine...if I haven't hooked you), please pick up this novel. 

There some deep felt feelings within this story. We get to know more about Zar (and someone new in his life), we get to know Mr. Spock more, and also learn lots about Adimiral Kirk and Dr. McCoy (and even some touching moments with Lt. Uhura).

Like I said at the top, this author LOVES Star Trek, and it shows. If you pick up this book, I truly feel you will have gained more appreciation (and love) for everyone on the Enterprise, especially Spock, Kirk, Bones and Uhura.
Profile Image for Lois Merritt.
406 reviews39 followers
June 17, 2019
This was okay. First, I barely have listened to a handful of the old Trek novels, let alone made it to like halfway or something, and this one is yet another with the Guardian of Forever. It's kind of annoying already. This one also had a prequel story to it, when Spock meets his son that he ended up having with Zarabeth from that TOS series episode, albeit taking place after the episode. This book doesn't need to have that one read first, but I think I would have liked it better if I did. So there are two things going on - there is a problem with the Guardian and Kirk and company were given back the Enterprise to go and fix it. (This is a month or so before ST2). They need someone who can talk telepathically to the Guardian, and that isn't Spock, but his son when we was here last, before he decided he had to go back to his time and place. So they go get him.

The stuff with Spock and his son was interesting, with a what-could-have-been if he did have children, but the time travel part, especially using the Guardian, really has gotten old with me, so I'm biased against that part of the story.
Profile Image for Sarah.
Author 43 books452 followers
April 4, 2022
Note: I listened to the abridged version of this novel.

This book is a good sequel and conclusion to Crispin's other book Yesterday's Son I listened to this audiobook one evening when I wasn't feeling well. I enjoyed the story a lot. I feel Crispin did a great job tying elements together from the series, movies, and her other book.


Content notes: minor cussing and inferred sexual activity.
Profile Image for Yvette.
102 reviews
Read
September 6, 2021
Another gem! Please listen to the hour plus audiobook with James Doohan and Leonard Nimoy.
Profile Image for Lesr Kew.
471 reviews20 followers
December 5, 2021
4.5 this was so good!

It had furry baby creatures.
It had love in a very deep intrinsic and “magical” way, soul-mate like status, and that is my favorite. obviously.
It had adventure and fast paced situations.
It was sentimental and honest.
It felt new and fresh, but also familiar.

Just so neat.

I only took off half star because specific instances sounds a bit hokey. Just expressions, at times. It would jerk me out of the book and bring me out of the story in those instances. But for most of the time, I was immersed.

well written!!
July 17, 2022
I honestly picked this book up because I saw it had The Guardian of Forever and Spock in the Maroon uniform. Had no idea that this was a sequel to a book Yesterday's Son about Spock's son. Now to read the first one.
Profile Image for Dean.
166 reviews
December 11, 2016
I was very surprised that I had not recorded this earlier.
Excellent book. The All my yesterday's series is definitely one of the all time me best StarTrek TOS mini series ever. Great characters that stay true to the original story line.
Profile Image for Andy Stjohn.
140 reviews2 followers
December 3, 2023
Now, this was an excellent book. A major, major improvement over the previous book which I just found ok.

This functions as a sequel to the book, Yesterday's Son where it is revealed that Spock has a son! During the events of All Our Yesterdays (which I rewatched after reading the first book again), Spock had a son with Zarabeth! Finding records of him in the ancient past, Spock sets out to rescue him and bring him to the present. However, Zar decides to stay in the past as he realizes he has an important role to play in Sapredion's history ( if I'm spelling that right).



This was an excellent book and the elements of high fantasy were great. The opening sequence of the crew saving McCoy from an expanding Alpha Centauri B was genuinely great. I will say the issue I had with the novel is that Zar felt like a bit of a Mary Sue, as he was able to do everything. He did download a lot of files from the Enterprise computer in order to allow him to survive, but it came off as he was just unstoppable. Kirk, Spock and McCoy also felt a little awkward in being placed in a fantasy setting, but it's quickly ironed out. I also wish Crispin had really played up the fantasy elements and had more fantastical creatures as that would have really cool to see how the crew reacted to it.



It was also cool to gain insight into the creators and the origin of the Guardian, as this is the only book to do that here. Also, Spock replacing him at the end to stop the prophecy was great and created a really interesting visual image. The banter between the main trio was great always, particularly when they were tied up.

Profile Image for Oleta Blaylock.
769 reviews7 followers
August 30, 2017
I think that this is one of my very favorite books in the Star Trek: TOS. This is a wonderful ending to the Yesterday Saga. I wish that there had been some way to have other adventures with Zar and Wynn. I always wished that he and Spock could have stayed together in the same time. I also wish that Zar had been able to meet Amanda and Sarek, As a warning there are some very sad parts to this story so tissues may be needed.

It has been 14.5 years since the crew of the Enterprise has seen Zar. Kirk has been promoted to Amiral after he save Earth from Vejar. Spock and McCoy are teaching at Starfleet Academy. Sulu is soon to be promoted to Captain and given his own ship. In this is time the Guardian of Forever is acting up and letting off waves of temporal distortion which is causing suns to die and the destruction of several starships and their crews. Other suns are aging to quickly and causing millions to have to be evacuated both the planet is consumed. Starfleet calls on Kirk and his crew to find out what is happening and fix it.

Kirk is beginning to realize that he would be much happier with a starship to command than he is being a administrator. He starts to wonder what it would take to get demoted back to captain. McCoy is also starting to long for the stars. This mission just reinforces that these people need to be out saving the universe not teaching and pushing paper.

After their first attempt to contact the Guardian ends in failure Kirk, Spock and McCoy decide to find Zar since he has contacted the Guardian previously. They find a disheartened Zar who is on the brink of a battle that he can't win. It takes some effort but they convince him to come back with them and try to fix the Guardian.

There is so much going on in this book. It is very well written and the characters are so real and identifiable. It was like a movie unfold. I just hope I can find more stories like this to keep my Start Trek addiction going.
Profile Image for Michel Siskoid Albert.
441 reviews5 followers
July 19, 2021
Ann Crispin's follow-up to Yesterday's Son, Time for Yesterday, is a longer and more mature work, and much more satisfying. We catch up with Spock's son Zar back in Sarpeidon's Ice Age, with some measure of world-building attached, and the introduction of, for my money, the best character of the book, Lady Wynn (no relation). Of course there's a reason for the regular cast to go back there and it's wrapped up in the origins of the Guardian of Forever, but even if the Enterprise's crew is well rendered (once again, Crispin gives Uhura a small but crucial role, which makes me happy), it's amazing how much we care about Zar off the back of Yesterday's Son (and of course, how his life has gone in the years since that book). Is it that we love Spock and see something of him in the character (in fact, I sort of cast him as an aging Ethan Peck who plays Spock in the Discovery era), or did Crispin endear him to us so completely in the span of her first short book? Perhaps a bit of both. Set just before The Wrath of Khan, it's a story that foreshadows Kirk's own relationship with a son. I think both books in the diptych have a nice claim to canonicity, not because they don't contradict much, but because their emotional core rings true and a worth being part of Spock's history.
Profile Image for George Eraclides.
210 reviews2 followers
October 4, 2020
A sequel to 'Yesterday's Son' by the same author. The Guardian of Forever is malfunctioning and its absence is destabilising the Space-Time fabric. The Federation leadership decides it needs an empath to try and communicate with the Guardian. Their first choice does not succeed and is badly 'damaged' so Kirk, Spock and McCoy go into the past again to find Zar, Spock's son (see Yesterday's Son for the full story), who is a high level empath (being the son of Spock). In the process they encounter the super-super-beings who created the Guardian, manage to save Zar from death and help him keep his Kingdom in Sarpeidon's past and, of course, succeed in their mission to save the universe. All in a day's work. Phew. These guys sure worked up a sweat. There is a lot of emotive clutter in the story or, if you prefer, 'romantic frisson', but the ideas are interesting and events sometimes strike a poignant note for old-time Trekkies like moi. My rating is because I am a fan of the original series and it is hard to disappoint me.
Profile Image for Lauren.
569 reviews6 followers
February 5, 2023
WOW, did AC Crispin really step up her game between Yesterday's Son and this sequel (published four years later). The prequel was fine but pretty much everything about this novel was better. I can't give it five stars because the pacing is a bit weird at the end; the main plot conflict wraps up 75 pages from the end and while the story is still engaging from that point, I'm not sure that it needed to be a full quarter of the book. While I like Zar there's a little bit more of him in his own timeline than I think we needed, but it's nice to see him again, and the Enterprise crew is well-represented here. A fun one for sure! I think it might be worth reading through Yesterday's Son just to get to the pleasure of reading this one.
Profile Image for Jamy.
55 reviews
March 14, 2021
Brilliant

The sequel to Yesterday’s Son (so if you have not read that go back and do so). The Guardian is malfunctioning and is causing the rapid aging of stars and destroying planets. Only one being alive can solve the problem and once again Admiral Kirk, Captain Spock, and McCoy must travel to the planet Sarpedian to locate and convince Spock’s son, Zar to return from his time to communicate with the time portal. The novel perfectly sets up the next adventure of the Enterprise and her crew, that being a little training/inspection cruise with a ship full of cadets. A great duology.
Profile Image for Susan Ray.
67 reviews1 follower
April 22, 2023
Good story line, but…

The plot was intriguing but the writing was difficult to read. It’s not that the author didn’t know how to put words together, but that whoever proofread the manuscript knew little, if anything, about punctuation and the correct use of quotation marks. Run-on sentences abounded and I had to stop and reread passages several times to discern what the author was trying to get at. I’ve found that frequently the proofreading for ebooks doesn’t measure up to that for a printed book. The Language Arts teacher in me wanted to correct the proofreading, but life is too short to recopy the book just for my own satisfaction.
Profile Image for Carol Palmer.
803 reviews14 followers
December 20, 2020
This novel is a sequel to Yesterday's Son and involves Spock's son Zar. This novel takes place after the events of Star Trek: The Motion Picture, but before Star Trek: The Wrath of Khan. Both movies are alluded to in the book. Although I read Yesterday's Son back in high school, it was easy to jump back into the story since I'm so familiar with all of the characters. It was a fun coincidence that while I was reading this novel that had the Guardian of Time as a major player, they also had the Guardian of Time on the most recent episode of Star Trek: Discovery.
Profile Image for Debbie.
342 reviews
April 7, 2024
See Yesterday's Son for my thoughts on books based on television shows.

Having no shame I also read the sequel. I didn't enjoy it nearly as much. My feeling is the very logical, pacifist Mr. Spock wouldn't be so sanguine about having a warlord son. I doubt that he would help with battlefield planning involving sword play.

I also had a hard time believing that the creators of the guardian would be petty, bickering fools.

Mainly, I'm upset that the only fanfictionish juiciness is Spock's son impregnating his warrior queen in a PG sort of way. That just doesn't cut it for me!
Profile Image for Amanda.
267 reviews
July 25, 2023
I enjoyed this book more then the first (Yesterdays Son) --> Spock's son Zar is more developed as a character then the first. Love how Crispin stayed true to the original characters while showing their maturity and bond both as a crew and friends. She made Spock embrace his human side and his son in a way that made sense for Spock and not a betrayal of who he was. An enjoyable book and well worth the read.
Profile Image for Kieran McAndrew.
2,292 reviews13 followers
March 19, 2019
The rate of entropy in the galaxy is increasing uncontrollably and Admiral Kirk soon discovers that something has gone drastically wrong at the planet codenamed Gateway. Only one person has made successful telepathic contact with the Guardian of Forever, Spock's son Zar.

Crispin's novel is a well paced adventure, which still manages to explore themes of family and duty.
Profile Image for Kevin.
772 reviews17 followers
September 3, 2020
A very good sequel to Crispin's Yesterday's Son. This continues where that left off. This time around Spock goes back in time once again, this time to save his son from dying in battle. It is a very well written novel that keeps the pace going at a decent rate. Definitely recommended for Trek fans, and also those who may not be into it very much, but knows the premise of the series.
Profile Image for F. William Davis.
846 reviews42 followers
July 1, 2021
I really enjoyed this. In some ways it didn't feel very much like a sequel because the events don't exactly follow on, but it was at least in the sense of checking in on Zar.

This story spends the bulk of the text on relationship building but I thought the most interesting parts were those dealing with the malady afflicting The Guardian of Forever.
929 reviews9 followers
April 17, 2022
This is one of those books were you know the entire plot 3 pages in. It was executing nicely, but not alot of surprises for sure. I think the main characters were just a bit too intimate with each other, too. I mean, they're older, so you can kinda go with it, but there are times it's a bit off.

Still, Zar is great fun, and it does follow nicely from the previous one.
Profile Image for Susan.
6,198 reviews56 followers
July 23, 2023
The Guardian of Forever is malfunctioning causing the death of planets. So Starfleet Command sends the Enterprise uniting Admiral James T. Kirk, Spock, and Dr. Leonard McCoy to investigate. This will send them back 5000 year to Sarpeidon and Zar. Who has his own problems to solve.
An entertaining story. Another re-read.
Profile Image for Michelle.
719 reviews12 followers
September 14, 2017
This was a fantastic addition to the Star Trek universe. The character voices were spot on and the adventure felt as compelling as one of the TV episodes. I was excited to see Zar again and I enjoyed how his story played out.
Displaying 1 - 30 of 83 reviews

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