Athrun
Athrun in the Justice assists Kira fight against the Forbidden, Raider, and Calamity. As the fight continues, the three Earth Alliance pilots argue with one another, but they are interrupted when they are struck by intense pain. The Earth Alliance are forced to retreat and regroup. The two friends reunite and Athrun must make a decision regarding whether he should continue obeying his father's orders or fight for what he believes in.
Aired 05/07/2003EP 39 - Athrun

Mobile Suit Gundam Seed
C.E. 71: In the midst of war between the Naturals (OMNI) and Coordinators (ZAFT), a unit from ZAFT is dispatched to hijack the Earth Alliance's newly developed mobile suits on the neutral colony of Heliopolis. Orb Civilian Coordinator Kira Yamato attends the technical college on Heliopolis. After ZAFT hijacks 4 of the 5 mobile suits, Kira stumbles upon the last one, Strike, forced to pilot it to save his and his friend's lives. During this confusion, Kira also reunites with his childhood Coordinator friend, Athrun Zala, who ironically turns out to be a ZAFT soldier and one of the hijackers at Heliopolis. Having control of Strike, Kira joins the Earth Alliance boarding the ship known as Archangel, to protect his friends while despairing over becoming the enemy of his childhood friend and people.
Note: An HD remaster was broadcasting starting on December 23, 2011 with two recap episodes cut, including new and updated animation, conversion to 16:9, and updated music.