Amazon Editors' favorite summer reads
$4.99 with 69 percent savings
Print List Price: $15.99

These promotions will be applied to this item:

Some promotions may be combined; others are not eligible to be combined with other offers. For details, please see the Terms & Conditions associated with these promotions.

Audiobook Price: $17.46

Save: $9.97 (57%)

You've subscribed to ! We will preorder your items within 24 hours of when they become available. When new books are released, we'll charge your default payment method for the lowest price available during the pre-order period.
Update your device or payment method, cancel individual pre-orders or your subscription at
Your Memberships & Subscriptions
Kindle app logo image

Download the free Kindle app and start reading Kindle books instantly on your smartphone, tablet, or computer - no Kindle device required.

Read instantly on your browser with Kindle for Web.

Using your mobile phone camera - scan the code below and download the Kindle app.

QR code to download the Kindle App

Follow the author

Something went wrong. Please try your request again later.

Critical Nexus (SimCavalier Book Four) (The SimCavalier series 4) Kindle Edition

4.7 out of 5 stars 18 ratings

Northern England, 2047. Jack Sladen, tech billionaire and local hero, is coming back to his roots. Cameron Silvera, hacker legend, doesn’t trust him. Is Jack out to save the world, or to destroy it?

The Sladen Foundation DAO seems like a great idea, but Cameron, the SimCavalier, has spent much of her infosec career tidying up the bugs and exploits in Jack’s software. Can he be trusted with this new venture, and why does he want Cameron’s help?

A new cybercrime outfit known as Steamyard is wreaking havoc in the digital realm and Cameron’s team are working all hours to keep their attacks at bay. As they dig deeper, they discover a disturbing connection between the Steamyard, the Sladen Foundation, and a convict held in isolation at the high-tech Way House Prison – a criminal artificial intelligence jailed two years previously for attacks on Cameron and her family.

Cameron knows that the only way to protect herself and her loved ones is to keep the rogue AI behind bars, but black hat hackers have other plans. As the Sladen Foundation celebrates its launch, the cybercriminals are revealed. Cameron and the Argentum team are in a race against time to stop the creation of a monster that threatens to take down everything they hold dear.

" I ripped through this book in a day, could not put it down!"
"... it picks up pace and impetus with every chapter."


Discover the SimCavalier adventures in ebook, audiobook and paperback worldwide.
Book 1:
Bitcoin Hurricane
Book 2:
Hacked Future
Book 3:
Tangled Fortunes
Book 4:
Critical Nexus
Book 5:
Unstable Realities
Book 6:
Quantum Breach - Coming Soon
Gridlock - A SimCavalier Short Story
Xanthe - A SimCavalier Short Story
Unwell Hydration from Alex Cooper
Hydrate & focus with every sip Shop now

Shop this series

 See full series
There are 5 books in this series.

Product details

  • ASIN ‏ : ‎ B09V1K1L59
  • Publisher ‏ : ‎ Sixth Element Publishing
  • Publication date ‏ : ‎ March 6, 2022
  • Language ‏ : ‎ English
  • File size ‏ : ‎ 1.4 MB
  • Simultaneous device usage ‏ : ‎ Unlimited
  • Screen Reader ‏ : ‎ Supported
  • Enhanced typesetting ‏ : ‎ Enabled
  • X-Ray ‏ : ‎ Not Enabled
  • Word Wise ‏ : ‎ Enabled
  • Print length ‏ : ‎ 346 pages
  • Page Flip ‏ : ‎ Enabled
  • Book 4 of 5 ‏ : ‎ The SimCavalier series
  • Customer Reviews:
    4.7 out of 5 stars 18 ratings

About the author

Follow authors to get new release updates, plus improved recommendations.
Kate Baucherel
Brief content visible, double tap to read full content.
Full content visible, double tap to read brief content.

​Kate writes novels and short stories that range from humorous sci-fi to dystopian visions, cybercrime and urban horror, and also serious non-fiction (as Kate R Baucherel).

She has been embedded in sci-fi since childhood, from her first glimpse of the Daleks from behind the sofa aged five through listening to the BBC Hitchhiker's Guide to the Galaxy broadcasts and being blown away by the first scenes of Star Wars on its original release. As a child she wrote her own Dr Who and Star Wars stories and occasional scripts for friends to act out in the park. She progressed to reading her dad’s collection of Wyndham, Bradbury, Clarke, Heinlein and Asimov before discovering Iain Banks, David Brin, Terry Pratchett and so much more. Kate works with emerging technologies and future visions and sometimes it's hard to separate the day job from fiction!

Customer reviews

4.7 out of 5 stars
18 global ratings

Review this product

Share your thoughts with other customers

Top reviews from the United States

  • Reviewed in the United States on December 30, 2022
    Baucherel's previous books in this series have been clever and full of misdirection. Book 4 dials up the intensity. I ripped through this book in a day, could not put it down!

Top reviews from other countries

  • C. K. Roebuck
    5.0 out of 5 stars Outstanding
    Reviewed in the United Kingdom on June 16, 2023
    Once more the Sim Cavalier does not disappoint. Loving the near future cybercrime series and this one has more intrigue than ever and a climatic ending to keep you hooked. Can't wait to start the next.
  • Lorraine
    5.0 out of 5 stars Enthralling story!
    Reviewed in the United Kingdom on July 14, 2022
    I love Kate's books. They teach me about what can go wrong if you ignore cyber security. It's fiction but has so much reality in it. It's a wonderful read and I alway wish that the next one was ready to read straight away :-)

Report an issue


Does this item contain inappropriate content?
Do you believe that this item violates a copyright?
Does this item contain quality or formatting issues?