The Giggle

The Giggle was an arpeggio, described as a "musical palindrome" by Melanie Bush, which consisted of the notes C, E, G, C, G, E, C in order. The arpeggio was in fact the laugh of Stooky Bill, a puppet used by John Logie Baird in his early experiments with television. The puppet was supplied by the Toymaker, who was able to "burn" the image and the associated giggle into every screen, carving a wave inside the heads of every human on Earth since 1925.

With the launch of KOSAT 5 in 2023, making the internet available everywhere on the planet, the Giggle became active and wreaked chaos, driving the human race mad by making everyone believe that they were right all the time in what the Toymaker considered to be the "game of the 21st century". The Giggle was stopped when UNIT shot down the KOSAT 5 satellite with the galvanic beam, thus putting an end to the transmission of the Giggle.

While the laugh was primarily associated with Stooky Bill, the Giggle was also the signature laugh of the Toymaker himself. (TV: The Giggle) Indeed, the Fifteenth Doctor would once again encounter the Giggle when facing against Maestro, the child of the Toymaker, who shared their father's signature laugh. Both the Toymaker and Maestro were members of what the Doctor referred to as the Pantheon, which comprised of "vast powers beyond the universe". (TV: The Devil's Chord)