Having studied all planets in the Sol system, Earth was chosen as the best to serve the Rutan Empire's plot to destroy the Sontarans. The scout made its way to Fang Rock and infiltrated its lighthouse. There it established the beacon and began to kill the lighthouse keepers and shipwreck survivors, one by one. Using recent Rutan technological developments, the Scout shape-shifted into the form of the lighthouse keeper Reuben. It electrocuted the others. Three regenerations later, the Doctor was forgiven by the Rutan Host for killing the scout. (PROSE: Shakedown)