"I'm absolutely delighted to be appearing in this new Doctor Who," Chris revealed. "The last time I appeared in Doctor Who was in 1986, Colin Baker was the Doctor and I was still a Young One."
If you did not know already the Sontarans are a famous monster from the classic series of Doctor Who. They first appeared in the episode The Time Warrior which ironically was Sarah Jane Smiths first story who was played by Elizabeth Sladen. Also last night if you were lucky enough to see Eye Of The Gorgon Part 1 on the CBBC channel the Sontarans were also mentioned.