Impossible Mission II - NES

According to the manual, Impossible Mission II puts you in control of an "Agency Field Agent" for Cobra Blue, a counter-terrorist operation that's trying to bring down the "psychotic genius" known as Dr. Elvin Atombender. 

Elvin lives in "an immense eight-tower complex constructed with his personal funds in northwest Los Angeles near the UCLA campus," "believed to be staffed entirely by robots of his own design." 

It's your job to infiltrate the tower and crack the security system so that you can put a stop to Dr. Atombender's plan to destroy the world. Each of the eight towers holds a piece of music locked away in a safe, and you need to collect all six unique tunes to unlock the central elevator control and reach Dr. Atombender. Two of the tunes are repeats, so you have to keep track of the ones you've already found with your tape recorder.