Lieutenant Alex (アレックス Areksu) was a military officer of the Organization of the Zodiac following the overthrow of the United Earth Sphere Alliance in the year A.C. 195. He was a radical supporter of the OZ movement and held a sadistic hatred for the UESA.
Holding a thirst for battle and having been radicalized by the ideals of Treize Khushrenada's OZ, Alex was a sadistic soldier who was eager to please OZ through the utter annihilation of the UESA's military forces. Alex had no regard whatsoever for human life and in battle attacked his enemies without hesitation nor mercy. He considered all opponents to be merely targets of OZ and would frequently fire upon his enemies even after they surrendered in battle. He considered "execution" missions a legitimate basis for the total annihilation of UESA forces, and even after achieving victory would eagerly massacre the survivors, laughing at their final moments.
Alex shared his hatred of UESA with his friend and squadmate Lieutenant Mueller, who often partnered up with Alex on their "executions".
Alex and Mueller were both students of former UESA instructor-turned OZ officer Lucrezia Noin, who taught them to fulfill the desires of OZ leader Treize Khushrenada, who masterminded UESA's overthrow. Upon UESA's fall, the two officers took command of OZ's forces on the Somalia Front, and initiated a campaign of terror against those forces still loyal to UESA, all in the name of Treize's revolution.
Alex and Mueller planned to destroy a major UESA facility off the coast of the Somalian capital of Mogadishu. Seeking veteran OZ pilots to ensure the success of their attack, they commissioned OZ Colonel Zechs Merquise to accompany their attack with his Tallgeese Mobile Suit. Zechs agreed to the mission, placing himself under Alex's command as his "subordinate". Deploying Zechs as a decoy in his more powerful Tallgeese Suit, Alex and Mueller planned to hit the base head-on while UESA fired their prized Noventa Cannon inland in an attempt to kill Zechs. Their plan in effect, the two pilots attacked the Mogadishu Base, annihilating its formidable defensive perimeter.
Zechs then called for the UESA forces to surrender peacefully as they had no further means of defense. Unfortunately, immediately after the UESA commander surrendered, Alex and Mueller pressed their attack, carrying out their next "execution". Appalled at this dishonorable display, Zechs turned on Alex's forces, killing Lieutenant Mueller in the process. Enraged, Alex attacked Zechs with his Cancer Suit, eventually forcing Zechs underwater in the Tallgeese. However, he had underestimated the abilities of both Zechs and the Tallgeese, and Colonel Zechs silenced Alex's rampage by killing the rampant Lieutenant.