“Parenthood had turned my life upside down and I was still trying to adjust to the huge emotional and psychological upheaval involved”, says Greenhorn, who also wrote the Doctor Who episodes ‘The Lazarus Experiment’ and ‘The Doctor’s Daughter’.

Marchlands tells the story of three different families living in the same house in the 1960’s, 1980’s and present day, all linked by the spirit of a young girl who died in mysterious circumstances. Starring Alex Kingston (Doctor Who) and Dean Andrews (Life On Mars), the five-part drama begins on ITV1 early next month.

“The first episode was written during the last few months of pregnancy. The other four in the first few months after my son was born,” Greenhorn continues. “You can imagine the environment – a combination of raging hormones and sleep-deprivation. A kind of altered-reality where things are never where you left them and your eyes and ears play tricks on you. A strange noise in the night. A movement on the edge of vision.

“This odd, uncertain state fed directly into the writing of the supernatural element and the way I chose to realise the ghost story. Even if you don’t believe in spooks, I think you can understand it as a reflection of the heightened emotions of the characters.”