Time capsule

A Dalek time capsule was a spacecraft that carried Dalek Factor.

During the final battle of the Last Great Time War, the capsule was sent to Earth to spread the Dalek Factor amongst humanity and use their life-force to create back-up from raw materials. The capsule's engines failed on the journey and the Dalek within ejected and fell to Earth in 70 where it released a small amount of Dalek Factor before dying. The Dalek Factor caught on to some humans and entered their genes, but was not active though it was always there, handed down from generation to generation until only 1 in 500,000,000 had it, including Kate Yates.

When the dead Dalek was unearthed, the Dalek Factor in Kate was activated and her Dalek life-force was used to create a new Dalek from the data stored in the casing of the Dalek from the time capsule. This Dalek attempted to continue the old plan, blackmailing the Doctor into giving it a Time Ring so it could travel to the year 500,000,000 with Kate and trick the peaceful humans there into giving it the raw materials it needed to rebuild its race.

However, Rose Tyler was able to reach Kate's human side and she set the Time Ring to self-destruct. The Dalek was killed in the warp implosion the self-destruct caused and all humans with active Dalek Factor from the presence of the Dalek went back to normal, including Kate. (PROSE: I Am a Dalek)