Macross Delta summary:

Macross Delta is set in the year 2067, eight years after the events of Macross Frontier in a remote part of the Milky Way Galaxy called the Brísingr Globular Cluster, which is plagued by the Var Syndrome, a mysterious phenomenon which turns people berserk without any apparent cause. A team of talented idols, the Walkure, uses the power of their songs to calm down the infected by the Var Syndrome, assisted by the Delta Flight, a team of experienced Valkyrie pilots. At the same time they are facing the interference from the Aerial Knights of the Windermere Kingdom, which found a way to exploit the infection in their favor as part of their plan to resume war against the New United Government for control of the Cluster.