SEARCHED PLAYERS FOR 'SOS'

Blood of the Cybermen: A worker at the base called Chisholm flees from the base on a Snowmobile where he finds a Cyberman arm. Chisholm falls off a cliff and gets badly hurt. The Doctor receives an SOS call which he responds to, and landing where Chisholm fell. The Doctor and Amy rescue Chisholm and they use the TARDIS where to go back to the base where Chisholm came from.