The once feared Cybermen have disappeared from the universe without trace. An expedition from Earth arrives on Telos - homeworld of the Cybermen - to try and discover exactly what has become of the silver giants.

Soon after the Doctor, Jamie and Victoria join the party, the first mysterious death occurs. With the group now stranded on Telos, it becomes clear that the Cybermen may not be as dead as it was first thought.

Beneath the planet's surface, giant ice tombs hold the last remains of the Cybermen in a frozen sleep. And someone is working to reactivate them from their slumber.

This story originally broadcast: 2nd/23rd September 1967

Producer: Peter Bryant
Directed by: Morris Barry