Written by Steven Moffat, it starred David Tennant and brought back Peter Davison as the Doctor.

[2] The Tenth Doctor tries to take off in the TARDIS after saying goodbye to Martha Jones, only for the time machine to spin wildly and sound an alarm.

The episode was first conceived by executive producers Julie Gardner and Russell T Davies, who decided to air an interstitial scene for Children in Need 2007.

Gardner asked Steven Moffat to write the special, with the stipulations the scene could be shot in one day and one set, and require no CGI effects.

A line about the effects of the paradox the TARDIS collision had caused gave an explanation of why the Fifth Doctor looked far older than normal, addressing that Davison had left the role over twenty years before.

The Tenth Doctor refers to Tegan Jovanka, Nyssa, the Cybermen stories Earthshock (1982) and "The Five Doctors" (1983), the Mara serials Kinda (1982) and Snakedance (1983), the Time Lords' "funny hats" from Arc of Infinity (1983), and the various Master stories during Davison's tenure.

Graeme Harper, director of Davison's final serial The Caves of Androzani (1984), directed the episode.

[10] Dek Hogan of Digital Spy mirrored Conaghan's beliefs; he called Moffat's script "witty" and hoped that Davison would return to film a full-length episode.