The Battle of Odessa is the twenty-fifth episode of Mobile Suit Gundam. It first aired on September 22, 1979 in Japan and on August 23, 2001 in North America.
Amuro and Sayla are preparing the G-Armor and Gundam for sortie. Amuro is still saddened by the death of Lt. Matilda and snaps at the technicians. He touches the G-Armor and slips into a reverie, which Sayla gently interrupts by reminding him that they have to sortie. Sayla's task is to provide reconnaissance on White Base's course, and Amuro accompanies her to assist her in gaining more experience operating the G-Armor. Fraw Bow asks Amuro if he's alright, but he ignores her.
The G-Armor launches. In the cockpit of the Gundam, Amuro has his copy of the picture that he took with Matilda pinned to the dashboard. Up on the bridge, Fraw reports to the communications console. Bright tells her that all he wants her to do is listen for an SOS signal. Elsewhere, M'Quve's forces are massing and preparing for battle. Gaia and Ortega fire into the air as tribute to their fallen comrade Mash. M'Quve snaps at them, thinking they are wasting their time and are only looking for revenge. Gaia and Ortega head out.
Amuro and Sayla continue to practice maneuvers in the G-Armor. On White Base's bridge, Fraw alerts Bright of an incoming message from General Revil. The message contains their orders for Operation Odessa, which are to charge into M'Quve's bases from the rear. Fraw is ordered to call the G-Armor back. Meanwhile, Amuro and Sayla have discovered the enemy's front line. Worrying that they may been seen, Amuro has Sayla lower their altitude. It is then that Sayla notices a small Federation propeller plane, the Dragonfly take off from Zeon territory. Despite their orders to return to White Base, Amuro and Sayla follow it, alerting Bright and Mirai who believe there to be a spy in the Federation.
With the enemy forces approaching, Bright orders their forces to sortie, despite Kai's protests. The Dragonfly lands on the Federation's Big Tray, which Amuro and Sayla follow. Upon landing on the Big Tray, Amuro is brought before General Elran and asks to speak to him alone. Outside, Federation soldiers hold Judoch at gunpoint and listen in. Amuro tells Elran about his belief that there is a spy, and provides a photograph as proof. Realizing that Judoch has been outed as a spy, Elran pulls out a gun on Amuro, believing that he can kill him without much of a worry due to his high rank. The Federation soldiers, who had been listening outside, shoot Elran through the door and take him into custody. Amuro yells at Elran for his role in selling out to the Zeon, which has resulted in the deaths of many such as Lt. Matilda. The Federation soldiers tells Amuro to head to the G-Armor and return to battle.
Operation Odessa begins, and the fighting is fierce. Kai and Hayato are entangled in their battle with Gaia and Ortega. Ortega angrily tells the accompanying Dopp forces to leave them alone so they can get revenge. The Guntank's tread is hit, forcing it to return to White Base. The G-Armor appears and assists in the battle. The G-Armor soon separates to release the Gundam, becoming the G-Fighter. When the G-Fighter is hit, Sayla returns to White Base where Hayato's Core Fighter is attached on the front.
M'Quve's forces are beaten back relatively easily, as they were counting on Elran to hold back the Federation forces on certain fronts. The remaining Black Tri-Stars also have their hands full taking on White Base and Gundam. Now desperate, M'Quve announces that he will launch a thermo-nuclear missile at the Federation forces if they don't withdraw, in violation of the Antarctic Treaty. Revil ignores the threat and has his forces move forward anyway. Amuro continues to fight Ortega and Gaia. He hops a ride on the G-Fighter and manages to defeat Ortega by chopping his Dom in half.
Bright alerts Amuro to M'Quve's intent to launch an nuclear missile. He provides Amuro with a schematic of the missile, telling him to slice off the detonator at the front so as to prevent its explosion. Amuro is worried, since he is still in battle with Gaia. M'Quve, realizing that the Federation has ignored his threat, launches the nuclear missile from the Dobday. Gaia attacks the Gundam, but Amuro gets the better of him and destroys his Dom. Amuro then sets his sights on the nuclear missile, and with the help of the G-Fighter is able to reach it. Gundam slices off the detonator on the missile and it harmlessly heads to the ground with a minor explosion.
The Federation Forces are victorious with Operation Odessa. M'Quve heads to space along with Uragang on the Black Tri-Star's Zanzibar, commenting that despite their loss, he has secured Kycilia enough resources to enable Zeon to fight for 10 more years. The battle over, the White Base crew is introduced to General Revil.
- Deceased: Gaia, Ortega
- The Battle of Odessa marks a turning point for the Federation in the One Year War.