Jon Pertwee, who would later say, "I have never liked the Daleks", felt that the monsters were very limited and could not understand their popularity. However, he would concede that the publicity, which followed the announcement of their return to the series by Barry Letts "was perhaps worth my biting my lip". On the other hand, he enjoyed working with the story's guest cast. He also liked the Ogrons, as unlike the Daleks, their design allowed the actors' mouths and lips to be seen and thus he felt allowed the actors playing them to "come to grips" with their characters and "with an entire range of expressions available" make the viewers believe in their performance. Pertwee also recalled he persuaded Barry Letts to include the trikes seen in the story, reflecting his love of vehicles. However he considered the chase sequence involving them to be "one of the more dangerous stunts that I had insisted on doing" during his time on the series.