6. 6955 kHz

Back "over here," Fringe Division investigates a bizarre phenomenon when 15 people up and down the Eastern Seaboard, all suffer retrograde amnesia from listening to their shortwave radios on the same frequency. Much to Walter's dismay, Peter presses on with piecing together the mass destruction device. Just as alternate Olivia and Peter's chemistry deepens, the anticipation of Olivia's return escalates.