Skip to content
Tropely
Theme
Catalyst Gate cover

Book guide

Catalyst Gate

by Megan E. O'Keefe

The gates are open, the code is cracked, and humanity is running out of time.

Buy or view on Amazon UK

As an Amazon Associate I earn from qualifying purchases.

About Catalyst Gate

The secrets of the Casimir gates have finally been revealed, but humanity is still in danger. Major Sanda Greeve and her crew must confront Rainier, an ancient alien intelligence determined to bring humanity down, in the explosive finale of the Protectorate trilogy.

Reading signals

Spice
Light
Darkness
Balanced
Pacing
Fast

Series

The Protectorate · Book 3 of 3

Content warnings
  • bodily harm
  • brainwashing
  • death
  • emotional trauma
  • self-harm
  • torture
  • gun violence
  • war
  • injury/injury detail
  • genocide
  • gore
  • medical trauma

Keep your next read close.

Save books, track your reading, and find more stories shaped around your taste.