The writing duo, who also co-created The League of Gentlemen and Psychoville, spoke to The Independent about the fifth run of their anthology show, which has gained popularity with each series.
The pair said they were ”mindful” about retaining the high quality of episodes and would only keep writing more if they believed they were able to pull it off.
“We want it to be good and don’t want ‘they’ve gone off the boil now’ to be the thing levelled at it,” Shearsmith said, adding: “That’d be a shame. If we think it’s become that, we’ll stop.”
Pemberton agreed, stating: “We’ll keep doing this until it’s not [well-regarded].”
The pair said that, if the idea warranted it, they would return to the worlds of previous episodes and revisit characters in future episodes.
When a crossover instalment featuring League of Gentlemen and Psychoville characters was floated to them, Shearsmith said: “It would be good if we went down that road.”
They also said they would return for more special episodes following the success of Christmas and Halloween editions should the BBC ask them.
“I like the idea of doing specials in an unexpected way, like a Pancake Day one,” Pemberton quipped. “I think all the holidays should have Inside No 9 episodes.”
Read the full interview with Pemberton and Shearsmith here.
Inside No 9 returns to BBC Two on Monday (3 February) at 10pm.
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