Bullen grew up in the West Midlands of England, attending the Solihull School and later Magdalene College, Cambridge. He left with a degree in history of art and became a radio producer for the BBC World Service. Unhappy with the quality of British television targeted at people his age, Bullen took a course in screenwriting and developed a one-off comedy drama for Granada Television.
Bullen's upbringing in the West Midlands of England at Solihull School and Magdalene College, Cambridge, led him to graduate with a degree in history of art. He then became a radio producer for the BBC World Service. Feeling underwhelmed by British television aimed at his age group, Bullen took screenwriting courses and created a one-off comedy drama for Granada Television.