There are 3 books in the The Protectorate series. The newest book is Catalyst Gate which came out in 2021.

1
Velocity Weapon

Book cover of Velocity Weapon
NOMINATED FOR THE PHILIP K. DICK AWARD FOR BEST NOVEL * Dazzling space battles, intergalactic politics, and rogue AI collide in Velocity Weapon, the first book in this epic space opera trilogy by award-winning author Megan O'Keefe.
Sanda and Biran Greeve were siblings destined for greatness. A high-flying sergeant, Sanda…
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2
Chaos Vector

Book cover of Chaos Vector

Dazzling space battles, intergalactic politics, and rogue AI collide in the second book in this epic space opera by award-winning author Megan O'Keefe.

Sanda and Tomas are fleeing for their lives after letting the most dangerous smartship in the universe run free. Now, unsure of who to trust, Sanda knows…

3
Catalyst Gate

Book cover of Catalyst Gate
The universe is under threat and an ancient alien intelligence threatens to bring humanity down unless Major Sanda Greeve and her crew can stop it in the final book of this explosive Philip K. Dick award nominated space opera.

The code has been cracked. The secrets of the Casimir gates…