Marko Kloos does not disappoint in this sci-fi thriller. Highly recommend for fans and those looking to become fans. Will be purchasing for library.

I have been anticipating the release of this book for a year. The author, Marko Kloos, said that the book was difficult to write in 2020 due to Covid 19 and frequent US political disruptions. It came out well, however. Kloos told the story from the perspective of four principal characters developed in the first book of the Palladium Wars series. Citadel is book three in that series.

After losing his former ship in the last book, Commander Dunstan Park is assigned to a new top-secret Rhodian navy experimental cruiser equipped with a powerful AI that can quickly hack into, and take over the computer systems of, any ship. He uses it to go after the unknown Rhodia attackers who blew up one of Rhodia’s cities killing hundreds of thousands of civilians. He partially accomplishes that.

Living under his false identity, Aden and the crew of a merchant ship he’s working on are attacked by an assassin in retribution for the crew turning over a nuclear device they found in their shipment to the authorities. One of his crew members, Tristan, was killed in the attack. Grieving the loss of their shipmate and friend, the crew set out to entrap the Gretian nationalists’ members who had anonymously hired them and then taken out a contract on their lives. They agreed to act as bait to draw the nationalists into a trap that would lead to their arrest by the Rhodesian Navy. The Navy was able to capture three nationalists’ ships with the fourth getting away.

Meanwhile, Idina Chaudhary is on Gretia, protecting the alliances’ occupying force. The Gretian nationalists attack an armored vehicle that she’s traveling in to protect an alliance dignitary. That same nationalist group then attacks and destroys the capital city’s police headquarters, almost killing Solveig Ragnar, Aden’s sister. At the end of this book, a task force of highly trained soldiers is established to root out and destroy the planet’s nationalists’ fighters.


Solveig returns from a successful diplomatic mission for Ragnar Industries and gets a greater amount of freedom from her father’s control. She can now openly go out with the handsome Gretian police detective introduced in the last book. Visiting him at the police headquarters canteen for a lunch date, the building is attacked and she is almost killed. As she recuperates, she learns that her father may have had some part in that attack. While that disclosure is hinted at, its story will not come out until the next book in this series.

The story in book three, Citadel, is alternately told from the perspective of each of these main characters. Kloos does a good job of keeping the storyline separate but the story increasingly coalesces around the guerilla war being waged by the Gretian nationalists. I hope that Kloos can wrap up the series in the next book as I don’t welcome book series that go on indefinitely, like Kloos’ Frontlines series for example.

Markos Kloos is a good military Sci-Fi writer who adds multi-dimension to his characters. Although they progressing slowly, his stories hold my interest and keep me reading. Kloos tends to use cliffhangers to assure that readers purchase the next book in a series. The primary cliffhanger at the end of Citadel is finding out what role the chief industrialist of Gretia has with the Gretian’s nationalist insurgency.

I enjoyed the third addition to the Palladium Series by Kloos. The book seamlessly fits the storyline. It's action packed and an easy read. I am looking forward to the sequel.

An excellent addition to this excellent series. I'm always glad for a new Marko Kloos, and this was no exception.

Thank you 47North and NetGalley for a copy of the eArc in exchange for an honest review. This is one of my most anticipated 2021 releases. While I really enjoy Mark Kloos' more well known series, Frontlines, this series is at a whole new level. It spans several human-settled worlds in a single solar system. The first book starts with the release of a POW, Aden, following a postwar imprisonment period. Aden is a Gretian. The Gretians lost the war to an alliance of the other planets in the system. He skips the conditions of his parole and joins a crew of a courier ship. This ship gets squashed between an uprising of Gretians against the alliance planets.

While Aden is a main focal point, there are three more POVs. Solveig, Aden's sister, is a vice president of Ragnar Industries, a powerful Gretian corporation. Idina is a Palladian soldier whose posting is to help keep the peace on Gretia between the occupying government and the Gretians. Lastly, there is Dunstan, a commander of an alliance warship keeping the peace of the alliance patrolled space. These POVs are mainly disparate, but start to tenuously come together with brief encounters between some of these characters.

The previous two books were fantastic. This book brings fast paced action and all the feelings. I cannot wait to hear about Book 4!

Citadel by Marko Kloos(Palladium Wars #3)-Highly recommended if you like energized Space Opera along with well developed characters, tense action, and intrigue. This series just keeps getting better with each book. I hope Kloos extends this story arc like he has with the equally enjoyable Frontlines books for many more entries

I received an ARC of this book from NetGalley for an honest review.

I have been a fan of Marko Kloos books for a while. the world is well built, the action is well paced and there is strong narrative to his books. Citadel was a great book, an easy read, and has depth. The story advanced, and there are a few plotlines that are coming together.

I would have given the book 5 stars if the story had advanced a little more, but I'm not sure we know an awful lot more than before we read the book. Not that the book was fun, compelling and exciting.

A very good read and looking forward to the next in the series.