So why has ARC suddenly commandeered the TARDIS, crossing back over its own timeline in one of the most dangerous stunts a time traveler can pull?! Has ARC been a sleeper agent all along, or are there deeper motives at work?
It's up to the Doctor and his companions to find out Ð if ARC doesn't wipe them all out first!
PLUS: the secrets of SERVEYOUinc's assault on the timeline revealed!