Speaking to the Telegraph, Fisher admitted:
"I had a Post-it-Note on the corner of my monitor that said, 'WWSMD; what would Steven Moffatt do? 'The answer was always, 'He would just write it better’, so I kind of just kept trying to do that."Another of the programme's executive producers, Steven Spielberg, is also a Doctor Who fan.
Extant, starring Halle Berry will air in the US on CBS and will be available on Amazon Instant Video in the UK.