Tensions increase as the peace talks approach, and Shane realizes that the enemy has learned details of Operation Roundhammer.

When the 58th is deployed to a moon to complete preparations for a major offensive, they encounter an unknown alien species.

The 58th is abandoned on a barren planet after a successful attack, leaving the marines to fend for themselves with no food---and no hope of rescue.

The 58th becomes embroiled in a top-secret counter offensive against the Chigs to help ensure the success of Operation Roundhammer.

While aboard the pleasure ship Bacchus for some R&R, the 58th receives a a sudden call to action.

Stranded on an embattled planet, the 58th discovers that it must race to reach a rendezvous point in time to save an injured Shane.

The arrival of the mail pouch from Earth holds bittersweet significance for each member of the 58th.

West discovers that his brother has enlisted in the Corps and is serving under a gung-ho lieutenant determined to make a name for himself as a soldier.

Conclusion. McQueen takes on what could be a suicide mission: find and destroy a seemingly invincible Chig superbomber.

Part 1 of two. Shane risks her life when she volunteers to fight with another squadron, led by a former boyfriend, against an enemy spacecraft.

Damphousse experiences a premonition that saves the lives of the 58th---and attracts the attention of a mysterious military branch that wants to exploit her apparent "powers."

Hawkes is stranded on an alien world when he accepts an assassination assignment that's supposed to buy him an immediate Honorable Discharge from the Marines.

Christmas Eve finds the 58th in dire straits: its transport vehicle is hurtling uncontrolled into enemy territory.

A failed mission on an embattled planet leaves Nathan suffering from head trauma and the rest of the 58th presumed dead.

The Marines are captured by Silicates after crash-landing in the Cerus System, and are jailed until McQueen and Cooper can rig a radio to call the Saratoga.

A commandeered alien ship provides the 58th with information about a Chig outpost, giving Earth forces an opportunity for a Trojan-horse attack against the enemy.

A supply mission goes awry, leaving the 58th stranded in alien territory and suffering from the effects of a mysterious Chig weapon.

UN officials board the Saratoga for an important conference which will determine the next Secretary General---of the world.

The 58th is forced to accompany a special-forces commando on what may prove to be a suicide mission---for everyone.

A mutiny aboard a cargo ship forces Cooper to make a difficult decision.

A sentry-duty assignment leads the 58th into a confrontation with a battalion of androids, among which are the AIs who murdered Shane's parents.

A survivor of the attack on the Tellus colony is found, leading West to believe that Kylen is still alive.

After decades of peace, mankind discovers that it is not alone in the universe and is pulled into a war with an unknown alien species. A group of new recruits in the United States Marine Corp are thrown into the heat of battle. They each joined for there own reason, but in the end they are all fighting for the same thing, Earth and the survival of the human race.