Kilgarriff would later play the giant robot in the Fourth Doctor’s first adventure, Robot, and would once again play the Cyber Controller in Attack of the Cybermen, this time with his own voice.

Letts watched Baker’s mesmerising performance as the villain in the movie, The Golden Voyage of Sinbad and found his new Doctor. Robot was ... as the addition of the Fourth Doctor’s face ...

in his debut story "Robot", he grabbed the audience's attention with his incredibly alien performance. And for seven seasons, he did not let go. Across countless adventures, the Fourth Doctor ...