Doctor Who Season 2 - Ep 3 - School Reunion (Patreon)

The Krillitanes - aliens with a mix-and-match physiology - are trying to crack the 'God-Maker', a paradigm to give them ultimate power. They are using children as a computer, and only the Doctor and Rose, re-united with Sarah Jane Smith and K9 can prevent them from becoming masters of time and space.