In a world devoid of music and under constant attack by monstrous creatures known as the Earless, Echo Rec is a boy who makes his living as a junk collector in his small town. One day, he stumbles upon a mysterious girl with an audio input jack on her body and no memories of her past. Turns out she possesses the rare ability of a Player, an individual capable of controlling mechs called Equipment.  The two embark on a journey of self discovery.