Visteen Krane was widely regarded as one of the greatest actors of his time. He was a very private man who shunned the visual medium, working mainly in the field of audio recording. One of his many performances was in the play The Good Soldiers.
Krane later turned to politics and eventually announced his candidacy for the Presidency. It was widely believed that he would win the election and would name his agent, Beth Pernell, as his running mate. In fact, Krane, finding Pernell's ruthless policies and ambitions abhorrent, planned to record a speech denouncing her. When Pernell discovered this, she had Hans Stengard shoot him in the head. His death was reported as a suicide and a tribute broadcast was planned to air a week later.
Although Krane's body died, he had earlier used the equipment in his sound suite to transfer his brain waves into the medium of sound. As a creature made of pure sound, it could perfectly reproduce any sound it heard and hide itself within any sound. It posed as research student Miles Napton while working with curator Gantman at the Museum of Aural Antiquities on Krane's body of work. Gantman, being blind, did not realise that he was working with a living sound wave.
When Amber Dent and Goff Fotherill broke into the Museum to alter recordings of Krane's speeches, Krane killed Fotherill and pursued Dent, demanding to know who had hired them. It then learned from analysing a recording of a phone conversation that Pernell was behind it and went after her. However, the Sixth Doctor, thinking the creature to be malevolent, trapped it on a holographic disc. Pernell secretly acquired the disc and tortured the creature by editing its waveform to find out everything it had done while free.
Krane escaped and, having been driven insane by Pernell's torture, planned to hide itself in the speech Pernell would give during the tribute broadcast, thus manifesting itself everywhere it was broadcast. The broadcast was blocked with an opposing waveform, which the Doctor believed would also kill the creature, but instead restored it to sanity. Krane and the Doctor then worked together to expose Pernell's crimes, and the creature decided to remain in the Museum to continue working with Gantman. (AUDIO: Whispers of Terror)