All of it started when the virus hit the earth and changed many into something that was later named the Variants. These Variants are bound to crush the human race which is collapsing fast. These three books which are combined here come after the end of the trilogy. In the first book of this set Nicholas Sansbury Smith informs the listeners about the creation of a new weapon by Dr. Kate and Dr. Pat. The team Ghost is fighting hard to save these two precious lives because they have no other chance to win the battle.
Master Sergeant Reed Beckham is gathering the men that are left after the fight. They have no hope of any help coming from the state they were once defending so they are on their own now. At the end of this fourth part, the two scientists realize that the weapon the two were developing might not be ample for the monsters. Bronson Pinchot starts narrating the fifth part right after the end of the fourth one.
Variants in this next part are shown as more powerful creatures. The president and the vice president also start thinking about a bioweapon that might be able to end the whole game forever. Reed also has no other option because the enemy is getting stronger and the battle looks to be slipping out of their hands.
In the last part present in this book set the same type of scenario is seen as it was witnessed in Hell Divers II: Ghosts and The Extinction Cycle Boxed Set. The battle has ended because the demons are destroyed but the reality is opposite to this situation. Reed is with Kate on the island and trying to live in complete leisure but he is unaware that deadly monsters are once again approaching.
