Original: In the series' narrative, Rose is introduced as a working class shop assistant from London, introduced alongside her own supporting cast in the form of her mother Jackie Tyler (Camille Coduri) and her boyfriend Mickey Smith (Noel Clarke).
Simplified: It is revealed that Rose herself is the Bad Wolf, the words being a message that she must return to the future to absorb the energies of the time vortex, saving the Doctor and the Earth from the Daleks.