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Big Sigma #4
Temporal Contingency
Temporal Contingency is the fourth book in the Big Sigma Series. Trevor “Lex” Alexander’s life has been less than blessed. In the past year he’s had to battle corrupt corporations, deranged techno-terrorists, and a robotic scourge. Now he’s received the opportunity to finally return to the racing career that had been cut short by some poor decisions. One could excuse him for not wanting to be embroiled in another insane adventure when he is so close to returning to his life’s calling. Sometimes the call of duty will not be denied. Karter Dee, a certified lunatic responsible for many of Lex’s recent woes, has discovered a threat on an unprecedented scale. He and Ma, his AI caretaker, know their plan to solve the problem will take a special mixture of competence, improvisation, and disregard for personal safety. Reluctance aside, Lex is the only man for the job. Even with the skilled pilot on the team, the scope of the problem has grown so massive that it may be unsolvable in its current state. Some would consider the situation hopeless, but any good engineer knows if you can’t find a solution, you have to change the problem. To give human society a chance at a future, Lex, Karter, and Ma, will have to venture into the past.
432 pages, Kindle Edition
First published March 24, 2016
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Displaying 1 - 30 of 32 reviews
August 20, 2026
Review to follow
June 12, 2020
Joseph R. Lallo doesn't just explore cool sci-fi and technically awesome concepts in his "Big Sigma series. He also incisively examines human social and ethical issues. I find myself intrigued by his characters and he has caught me totally by surprise several times. For one thing, I have had to plead guilty to a common tech-head flaw: technical coolness and raw genius does not a hero make! Neither does genius imply wisdom. And, basic decency and an ethically motivated approach to life should never be undervalued!
There's plenty to enjoy in Temporal Contingency. Lallo has some very interesting thoughts on time travel. His examination of the boundaries between human and artificial intelligence are both intelligent and sensitive. Not to be forgotten is that Lallo's writing is humorous and very readable.
This volume is very important to the storyline, so don't miss it!
Highly recommended!
There's plenty to enjoy in Temporal Contingency. Lallo has some very interesting thoughts on time travel. His examination of the boundaries between human and artificial intelligence are both intelligent and sensitive. Not to be forgotten is that Lallo's writing is humorous and very readable.
This volume is very important to the storyline, so don't miss it!
Highly recommended!
October 13, 2018
Another great addition to this incredible series.
I'm not usually a fan of temporal sci-fi stuff as most of what's out there tends to run up its own arse and leave the reader or viewer with their heads shoved up there's, but this book doesn't feel like that - Joseph plays some great temporal 'get out of jail free cards' that certainly worked for me.
And he's really pushing the boat out with 'Ma' on this one. She's definitely become my favourite fictional AI.
Anyways, great stuff, and can't wait for Big Sigma #5 and the next chapter in Ma's life - which i hope isn't too long in coming.
I'm not usually a fan of temporal sci-fi stuff as most of what's out there tends to run up its own arse and leave the reader or viewer with their heads shoved up there's, but this book doesn't feel like that - Joseph plays some great temporal 'get out of jail free cards' that certainly worked for me.
And he's really pushing the boat out with 'Ma' on this one. She's definitely become my favourite fictional AI.
Anyways, great stuff, and can't wait for Big Sigma #5 and the next chapter in Ma's life - which i hope isn't too long in coming.
July 30, 2017
I couldn't stop reading - from beginning to end!
This book is just as addictive as the others in the Big Signs series,perhaps even more so. I'm normally not a huge fan of time travel books,but this one is so well done that i recant my usual positron and say i loved every word of it! I'm not going to go into the details of the plot. You can read the synopsis for that, but I will say that you should get this book and the others in the Big Signs series now, now, now!
This book is just as addictive as the others in the Big Signs series,perhaps even more so. I'm normally not a huge fan of time travel books,but this one is so well done that i recant my usual positron and say i loved every word of it! I'm not going to go into the details of the plot. You can read the synopsis for that, but I will say that you should get this book and the others in the Big Signs series now, now, now!
June 17, 2025
3 stars. For the most part, I've enjoyed this series. However, with this book I finally have reached the end. I like the odd characters. I like the amusing interactions. I like the plot and story twists and turns. All until I didn't. It all just eventually seemed repetitive and pointless. For me, this series just became a top spinning around: initially exciting but eventually nothing but the same boring action until eventually the top loses momentum, wobbles, and falls over.
March 9, 2018
Can’t tell if this is the last in the series or not. It was a fun ride. Lex has to again save the world - a bit more complicated scenario this time. Man continues to grow toward human. Karter is still Karter.
July 2, 2018
Brilliant
Loved every book shame no more in the series but well received by me. Keep up the good work. Thanks
Loved every book shame no more in the series but well received by me. Keep up the good work. Thanks
October 20, 2018
This book involves time travel, and it plays with all the issues time travel causes.
February 19, 2019
Time travel and VonNeuman machines!
What could be better! Somehow I don't think our hero is finished yet. Time causality and all. Author keeps you guessing.
What could be better! Somehow I don't think our hero is finished yet. Time causality and all. Author keeps you guessing.
August 6, 2019
Most Amazing Story
My favorite story in this series, is book #4 - "Temporal Contingency". Especially the 'singularity weapon'. Thank you Mr Lallo! That piece alone made my summer! The characters are so wonderfully written. I get so into the story - I don't just "read the book," I live the story. I've lived in Middle Earth and Pern. And now in Lex's world, with Ma and Karter.
My favorite story in this series, is book #4 - "Temporal Contingency". Especially the 'singularity weapon'. Thank you Mr Lallo! That piece alone made my summer! The characters are so wonderfully written. I get so into the story - I don't just "read the book," I live the story. I've lived in Middle Earth and Pern. And now in Lex's world, with Ma and Karter.
August 17, 2019
i usually hate (spoiler) time travel plots. but this one was bearable. especially with 3 instances of Ma.
August 26, 2020
I knew it, I've been shipping Lex and Ma from the start. Pretty nice that it (sort of?) happened.
This entire review has been hidden because of spoilers.
May 21, 2021
I’m addicted to this series! My mind keeps getting blown repeatedly! Of course I’ve purchased the next book! How could I not?
July 20, 2021
Wow. And, just for the record, I was wrong in my guess about the cover art.
September 28, 2022
Great read
Great read and flow of story. Looking to read the next book in the series. Keep on writing sci-fi books
Great read and flow of story. Looking to read the next book in the series. Keep on writing sci-fi books
February 16, 2017
Back and forth to the future.
Great read. Lots of action with some very deep thinking by way of explaining how the improbable might work.
Yes
Great read. Lots of action with some very deep thinking by way of explaining how the improbable might work.
Yes
March 2, 2016
I am a fan of this author's work. I really enjoyed his prior books in this series and his Deacon fantasy series.
In Book 4, our hero grows up a little bit and Ma, the computer grows a lot. Once again Lex is saving the universe, our crazy engineer/scientist is even "madder" in his crazy way, and we get to visit the past, present, and future.The scope of the plot was larger than Lallo's prior books in the series and was well done. It didn't have quite the same level of humor or laughs that his prior Big Sigma books gave me, but it's still a 5-star book in a great series that will appeal to every space opera science fiction fan and anyone that likes the old fashioned type of sci-fi story. Aficionados of heros, spaceships, computers, crazy scientists, world and universe building will enjoy the Big Sigma series.
In Book 4, our hero grows up a little bit and Ma, the computer grows a lot. Once again Lex is saving the universe, our crazy engineer/scientist is even "madder" in his crazy way, and we get to visit the past, present, and future.The scope of the plot was larger than Lallo's prior books in the series and was well done. It didn't have quite the same level of humor or laughs that his prior Big Sigma books gave me, but it's still a 5-star book in a great series that will appeal to every space opera science fiction fan and anyone that likes the old fashioned type of sci-fi story. Aficionados of heros, spaceships, computers, crazy scientists, world and universe building will enjoy the Big Sigma series.
July 11, 2016
I have become a big fan of Joseph Lallo's sci-fi and steampunk work (I don't do fantasy). He has a light touch with his science that serves the story but it always seems to be well grounded in current scientific understanding. At the same time his character development shows a lot of care and attention, dialogue retains (sometimes dramatically) different thought processes and delivery styles. Interactions between Lex, Ma and especially Karter are bound to make you do a double-take.
There is a fair bit of growth in the characters in this novel. The next book will have the characters approach their tasks and relationships much differently because of the story here. Except Karter of course because he's just off the rails.
A very satisfying and fun book that leaves just enough threads to pick up on the next time around.
There is a fair bit of growth in the characters in this novel. The next book will have the characters approach their tasks and relationships much differently because of the story here. Except Karter of course because he's just off the rails.
A very satisfying and fun book that leaves just enough threads to pick up on the next time around.
May 3, 2016
Just as good as the others, and a time travel story I have no quibbles with. (Which is high praise indeed, coming from me.) The present already incorporates any and all "changes" the time traveler is going back to make. What will happen has already happened, so the present is the result of the changes.
It's a difficult plot to write well, and Lallo pulls it off. My compliments to him.
It's a difficult plot to write well, and Lallo pulls it off. My compliments to him.
June 25, 2016
So good!
I can't even explain why I enjoy these books so much. Maybe because Lex is such a great guy... I know I love his interactions with the many iterations of Ma and one of my hopes for his future is that he ditches Michella and marries Ma in her human form - probably not likely, but I can still hope...
I can't even explain why I enjoy these books so much. Maybe because Lex is such a great guy... I know I love his interactions with the many iterations of Ma and one of my hopes for his future is that he ditches Michella and marries Ma in her human form - probably not likely, but I can still hope...
November 9, 2017
Terrific book by an outstanding story teller.
At last a time travel story that covers and handles ALL the complications and paradoxes with mastery. This is a series I'm sure to reread many times. It's packed with great action, emotion with the salvation of the entire galaxy on the line.
At last a time travel story that covers and handles ALL the complications and paradoxes with mastery. This is a series I'm sure to reread many times. It's packed with great action, emotion with the salvation of the entire galaxy on the line.
April 9, 2016
Mr. Lallo delivers again
I hope there are many more books to come in this series as each story has been fantastic! This one was no exception. They just steadily get better and better and that, in itself, is a feat!
I hope there are many more books to come in this series as each story has been fantastic! This one was no exception. They just steadily get better and better and that, in itself, is a feat!
May 30, 2016
Temporal Contingency review
A well told edge of your seat tale with surprising elements of humor. At times I got lost in the explanations of technology and time travel. The characters were believable. Overall a good read.
A well told edge of your seat tale with surprising elements of humor. At times I got lost in the explanations of technology and time travel. The characters were believable. Overall a good read.
January 4, 2017
Has to be my favorite series of books out there right now. The stories are great but it's really the characters that I love. This one has extra doses of the AI character, Ma. That aspect probably pushes this to my favorite book in the series.
April 12, 2016
I really like this series and feel like this was a fitting addition. I'm especially fascinated with compelling AI characters (of which there are a few).
May 1, 2016
This book really took things to the next level! I need book 5 ASAP!
May 23, 2016
Another solid entry in the Big Sigma series.
October 28, 2016
Awesome thank you
I was so so excited to see another book. This is even better then the rest. I hope there will be more.
I was so so excited to see another book. This is even better then the rest. I hope there will be more.
December 13, 2016
This was really fun exploring the time travel paradox with Ma and Lex.
March 19, 2017
I struggled with this one a bit at first. But it turned out to be great. I hope there are more in the series sometime. I would love to see events from the other perspective.
Displaying 1 - 30 of 32 reviews





















