On screen, Doctor Who is a story of monsters, imagination and mind-expanding adventure. But the off-screen story is equally extraordinary - a tale of failed monks, war heroes, 1960s polyamory and self-sabotaging broadcasting executives. From the politics of fandom to the inner struggles of the BBC, thousands of people have given part of themselves - and sometimes, too much of themselves - to bring this unlikeliest of folk heroes to life.

This is a story of change, mystery and the importance of imaginary characters in our lives. Able to evolve and adapt more radically than any other fiction, Doctor Who has acted as a mirror to more than six decades of social, technological and cultural change while always remaining a central fixture of the British imagination. In Exterminate / Regenerate, John Higgs invites us into his TARDIS on a journey to discover how ideas emerge and survive despite the odds, why we are so addicted to fiction, and why this wonderful wandering time traveller means so much to so many.