"Planet of the Dead" is the first of four special episodes of the British science fiction television series Doctor Who broadcast between mid-2009 and early 2010. It was simultaneously broadcast on BBC One and BBC HD on 11 April 2009. The specials served as lead actor David Tennant's final stories as the Tenth Doctor. He is joined in the episode by actress Michelle Ryan, who plays Lady Christina de Souza, a one-off companion to the Doctor. The episode was written by Russell T Davies and Gareth Roberts, the first co-writing credit since the show's revival in 2005. "Planet of the Dead" serves as the 200th story of Doctor Who.

The episode depicts Christina fleeing the police from a museum robbery by boarding a bus that accidentally travels from London to the desert planet of San Helios, trapping her, the Doctor, and several passengers on board the damaged vehicle. After the bus driver dies trying to return to Earth, the Unified Intelligence Taskforce, headed by Captain Erisa Magambo (Noma Dumezweni) and scientific advisor Malcolm Taylor (Lee Evans), attempt to return the bus while preventing a race of metallic stingray aliens from posing a threat to Earth. At the end of the episode, one of the passengers delivers a warning to the Doctor that "he will knock four times", foreshadowing the remaining three specials.

"Planet of the Dead" was the first Doctor Who episode to be filmed in high definition, after a positive reaction to the visual quality of spin-off series Torchwood and the financial viability of HDTV convinced the production team to switch formats. To ensure that the desert scenes looked as realistic as possible, the production team filmed in Dubai for three days, sending several props, including a 1980 double-decker Bristol VR bus, to the United Arab Emirates for filming. After a shipping container unintentionally damaged the bus in Dubai, Davies rewrote the script to explain the damage in the narrative.

The audience gave the episode an Appreciation Index of 88—considered excellent.