They are asked to defend not only their planet but the entire planetary system. Among the stars, it is predicted that strange aliens are planning against the planet. If the conspiracy is true then sooner or later the planet will suffer big time. It is better to attack the enemy when it is not prepared fully. New allies are made as Gareth Armstrong takes the narration to the next gear.
Something like Dark Angels (German edition) will be there in the story all the time but the theme will run as an independent thing throughout. Great warriors and epic fights just garnish all the main scenes of this book. No one will ever want to skip any of the fight scenes if he is a true fiction lover. The two new warriors accomplish their goals but after a lot of hard work.