Kaine's Sanction

He was trained to follow orders. Now he has to give them.
Disgraced Academy graduate Hayden Kaine reports for his first posting as second lieutenant aboard the ageing UEF cruiser Scimitar, bound for the forbidden Mu Arae system to recover a missing historian and his research on the long-dead Glenatat.
It should be a routine run. It isn't.
The Scimitar is attacked by the Malliac — invisible dark-matter aliens who reduced the colony world Dulcinea to lava forty years ago, and whom no conventional weapon can touch. The captain is incapacitated. The crew is dying. And beyond the ancient Glenatat star-gate, some thirty Malliac warships are amassing — preparing to hack the jump-gate network itself.
If they succeed: billions dead, and humanity hunted into extinction.
Kaine's only play is unthinkable: destroy the entire faster-than-light network with his own hands — cut off the beating pulse of human civilisation — and make himself the most hated man in human history.
"If we succeed, we will become the most vilified group in human history."
No good options. Still has to choose.
What you will find inside:
Fast-paced military science fiction with no filler
Competent people under extreme pressure
Command decisions where every choice costs something
A shipboard crew that earns every inch of survival
First contact with a truly alien enemy
A complete story in every book — no cliffhangers
For readers of The Expanse who like their officers competent and their consequences permanent.
Kaine's Sanction is Book 1 of Shattered Empire — six novels, one complete story.