When Jyden met the First Doctor, Ian Chesterton, Barbara Wright and Susan Foreman, the figures of Thal legend, he convinced Susan to explore the seemingly-abandoned Dalek City with him. Together, they uncovered a secret level beneath the city, revealing to the Thals that some of the Daleks had survived. He was unaware his mother had been convinced to aid the Daleks and flatly refused to believe she would do such a thing after it was revealed to him.
When the Daleks raised an army to attack the Thal City, Jyden disguised himself in an empty Dalek casing and escorted Ian to the Dalek City, pretending he was a prisoner. He fought off the Dalek Supreme, rescuing the Doctor and Susan, but he arrived to late to save his mother. He continued to help the travellers in fending off the Dalek attack on the Thal City. (AUDIO: Return to Skaro)