Set to air as Episode 4 of Series 6, ‘The Doctor’s Wife’ stars Suranne Jones (Coronation Street) as a character named Idris.

Discussing how he found working within the show’s budget in an interview with SFX for the magazine’s next issue, Gaiman explained: “The nature of the beast is that on the page you have infinite time and infinite money. In reality… But there are things that happen for budget reasons that actually make things better.”

The fantasy writer continued: “In my episode I get to bring back a classic monster. I didn’t plan to bring back a classic monster. I tried to create a completely new monster. But shortly before shooting it became very apparent that given the incredible amount of money they were going to have to spend on my episode… there came a point where they said, ‘Look, we cannot stretch to doing this prosthetic stuff that you wanted, would you like a classic monster?’ So we got to take a Russell monster and bring it back, which made me incredibly happy, in a weird way.”

He added: “It was a nice link between the Tennant era and the current era, and it was nice to bring it back and do something very different with it, turn it upside down.”

Gaiman has described the finished episode as “scary and it’s exciting and it’s heartbreaking” and recently revealed that around 13 minutes of scenes shot for the episode had to be left out of the final cut.