Escape From Side 7
The assault carrier White Base arrives at the remote Side 7 space colony to collect the Earth Federation's new prototype mobile suits. However, the White Base has been detected by a Zeon cruiser commanded by the cunning Char Aznable, who sends a team of Zaku mobile suits into the colony. The attackers begin wiping out the Federation defenders, until a young civilian named Amuro Ray activates the prototype Gundam and destroys two of the Zakus.

With most of the Federation soldiers lost in the Zeon attack, a new White Base crew is hastily formed from cadets and civilian volunteers, among them a young woman named Sayla Mass and junior officer Bright Noa, who becomes the ship's acting captain. The White Base escapes Side 7, carrying with it the surviving prototype machines and a host of civilian refugees. The crew seek refuge at the Luna II base, but are instead ordered to continue on to the Federation's Jaburo headquarters in South America.

North America
As the White Base enters the atmosphere, a surprise attack by Char drives the ship far off course, and it descends over Zeon territory in North America. Char contacts his old friend Garma Zabi, the youngest son of Zeon's ruling family and the nominal commander of its terrestrial forces, and the pair begin pursuing the Federation vessel across the continent. But during Garma's final attack, Char leads his friend right into the White Base's ambush.

Sovereign Degwin Zabi is devastated by the loss of his beloved son Garma, but his remaining children vary greatly in their reactions. Degwin's oldest son Gihren, supreme commander of the Zeon military, turns Garma's funeral into a propaganda rally. Younger son Dozle dispatches the ace pilot Ramba Ral to avenge Garma by hunting down the White Base. And Degwin's daughter Kycilia, learning that Char has been discharged for his failure to protect Garma, recruits him into her own service.

Operation Odessa
Though the White Base has now escaped Zeon-controlled North America, its journey is far from over. The ship is ordered to continue west and join Operation Odessa, a major offensive in which Federation forces led by General Revil hope to capture Zeon's Central Asian resource mines. As the White Base makes its way towards Odessa, its crew must deal with both Ramba Ral's pursuit and the new threat of Zeon's elite Black Tri-Stars team, and many of their comrades fall in battle.

The Odessa campaign ends in victory for the Federation, and Zeon's terrestrial forces begin to collapse in its aftermath. The White Base resumes its westward journey, pausing at a Federation base in Belfast, Ireland where the crew are introduced to their patron General Revil. Here they also draw the attention of their old enemy Char, now the commander of a Zeon submarine squadron, who follows the ship as it continues on to Jaburo.