Therefore, its known narrative elements are not a part of the Doctor Who universe as we, on this Wiki, choose to define it. It may have been the basis for a similar story in another medium, however — and that story may indeed be valid.
Deadline to Doomsday was a Doctor Who Magazine back-up comic which was under production with Ron Turner, the artist of the original TV Century 21's The Dalek Chronicles, when the artist passed away. The first two pages, with no text or header art, were printed in the end of Doctor Who Magazine 276 among an article remembering Turner.
Years later, the comic was completed by artist Lee Sullivan, colourist Charlie Kirchoff, and letterer Richard Starkings according to John Lawrence's original script and published in the third issue of the fan magazine Vworp Vworp!
Following their failed invasion of Earth in Return of the Elders, the Daleks pass through a strange energy field on their return trip to Skaro. While they believed the field to be harmless, upon their arrival, they discover that it caused a navigational error and they are instead on an unfamiliar planet. Before they can leave, they are shot down and crash, ruining their propulsion system.
Almost immediately they are attacked by metal-armoured humanoid scavengers riding dinosaurs; after a brief skirmish, the Daleks subdue the attackers and the Emperor interrogates their leader, Gorath. Gorath explains that this is the planet Kero, where the K'laats and Tarls are battling for supremacy. Gorath's people, the Mogari, are caught in the crossfire of this war, frequently enslaved by the K'laats to mine the mineral borillium.
Gorath takes the Daleks to the Mogari village, which is built of scavenged spacecraft. The village elder Logar resists the Dalek demands, but after an execution, the Daleks take the materials they need to repair their propulsion unit. All that is left is the fuel, borillium. The Daleks invade the Tarl city through its catacombs, and after a valiant-yet-futile resistance effort, the Dalek Emperor reaches an agreement with the Tarl leader Garon to destroy the K'laats in exchange for the Tarl's borillium. The Daleks launch their burrowing bombs toward the K'laat city and prepare to depart.
However, as they exit, the Daleks notice a crashed K'laat ship. Its blue-skinned pilot resembles a humanoid Dalek! After a quick analysis of Kero's star patterns, the Daleks realise that the energy field was actually a temporal anomaly: Kero is the ancient past of the planet Skaro, when the Thals were known as Tarls and the Daleks as K'laats. The Daleks quickly identify the positions of the burrowing bombs and dig a ravine so they can safely detonate far from the city of their ancestors. The Emperor's ship then travels back through the temporal anomaly and returns to the intact Skaro City to begin preparations for a new invasion of Earth.
- This story references the account of the creation of the Daleks originally presented in the TV Century 21 The Daleks comics. Differing accounts were given in the television serial Genesis of the Daleks and the short story We are the Daleks!.