In the late 1970s, Blue, a woman with feline features, utilizes her unique talent for ghost-seeing and her skill in wielding three guns with her tail to solve numerous mysteries and challenges. When two couriers, Bill and Robert, fall victim to a puzzling attack by masked assailants, Blue delves into the mystery. Surprisingly, the attackers' target is a Sinatra cassette tape owned by Bill. Thus unfolds a day filled with unexpected twists and turns as the importance of this seemingly ordinary tape comes to light.