The Swifts were a musical group. Its members were Nick Swift, Speedy, and Jock. The Master hypnotised them and made them create a new group, The Four Horsemen.
A record produced by the new group was played on the radio. Subliminal messages in it made all those listening want to go to Stonehenge. The Master's plans were stopped by the Third Doctor and Brigadier Alistair Gordon Lethbridge-Stewart. (PROSE: Smash Hit)