The most mysterious of the Gundam pilots, the young man who calls himself Trowa was sent to Earth as the pilot of the Gundam Heavyarms. The cool, quiet Trowa has nerves of steel and superb reflexes, qualities which serve him well in his cover identity as an acrobatic clown in a traveling circus troupe. He also has soldiering experience far beyond his years. When combined with his heavily-armed Gundam, Trowa's tactical skill and combat ability make him a veritable one-man army.

Still touring the world with his traveling circus, this former guerilla warrior is content with his new life as an acrobatic clown. However, when the circus visits the space colony X-18999, Trowa's path once again crosses that of the Barton Foundation, and he is drawn into the gathering conflict. As he did in the war against OZ, Trowa infiltrates the enemy army to foil their evil schemes from within.