According to an article in todays Sunday Times, Steven Moffat has set the challenge to his team of writers to come up with an episode set entirely within the confines of the TARDIS.
Given the current multi series story of the TARDIS possibly being controlled by some sort of external force, known by fans as 'The Voice', this could be a strong contender for one of the 13 slots available for Series 6, though obviously nothing has been confirmed.
The last time the show had a story set entirely inside the TARDIS was The Edge Of Destruction in 1964. It was the third ever televised Doctor Who story.
Would you be happy to see a story set entirely in the TARDIS? Let us know.