Sometime in the 22nd century, humans have fullyย terraformedย and colonized Venus and Mars. The Neosapiens, an artificially engineered race created to beย slavesย for the Terrans, haveย turned against their mastersย and formed theย Neosapien Order/Empire/Commonwealth. Under the rule of the calculatingย Governor General Phaeton, the Neosapiens have launched an invasion of Earth and Venus. The ExoFleet, the Homeworlds' space navy (in particular, Able Squad, a group ofย Exo-Frameย pilots led by Lieutenant J.T. Marsh), fight against the invasion in an interplanetary war to protect the Terrans.