A spin-off of the anime series Macross Δ. Takes place 5 years prior to the events in the anime.

After the end of the Vajra War in A.D. 2059, a mysterious disease known as Vár Syndrome began infecting various parts of the galaxy. It afflicted all forms of life, including the once peaceful gargantuan Una-mushi(Eel Bug), causing it to go berserk and terrorizing the local populace on the planet Pipré. In A.D. 2062, Chaos' Pipré Branch, an interplanetary para-military contractor charged with security of Pipré, began an experiment using the female idol group Thrones to demonstrate the power of Song and the power of their "Fold Receptors" to counteract the effects of the Var. Thus begins "Project Thrones".

(Source: Macross Wiki)