[s0e9] The Next Doctor Official

: The episode famously features a low-tech Victorian "TARDIS," which stands for T ethered A erial R elease D eveloped I n S tyle—a hot air balloon used by David Morrissey's character.

: While earlier stories like "The Unquiet Dead" were set in the past, this was the first revived-series Christmas special to take place in a past era (1851 London) rather than the present day. [S0E9] The Next Doctor

: Guest star David Morrissey was reportedly cast only five days before filming began. : The episode famously features a low-tech Victorian

: This was the last episode of Doctor Who to be produced and broadcast in standard definition. [S0E9] The Next Doctor

: The set for the Cyberfactory was actually the reused and disguised Torchwood Hub set from the spin-off series Torchwood .