Eric Marsden was a moderately successful musician from the 1960s and 70s who recorded a song, never released, that evoked feelings of love and happiness from the primal part of the brain, allowing bank robbers (including his old producer and his daughter Stephanie) to play the song and simply ask for the money. It would only have the desired effect in buildings with tall hallways and marble or other resonant materials in the walls.
Since he lost the rights to his recordings, he has become semi-catatonic, bipolar, and developed liver cancer. His caretaker warns Myka and Pete about their phones going off, or vibrating. Apparently Myka's voice has a pleasant timbre, while Pete's voice would upset Marsden. His conversation is, however, rather rambling, and generally uninformative.
After the bank robberies are successful, Myka and Pete track down the robbers to Eric Marsden's home, where he sits with his old recordings.