Partners in Crime (Doctor Who)

"Partners in Crime" is the first episode of the fourth series of the British science fiction television series Doctor Who. It was broadcast on BBC One on 5 April 2008. The episode reintroduced actor and comedian Catherine Tate as Donna Noble, who had previously appeared in the 2006 Christmas Special "The Runaway Bride". In the episode, Donna and the alien time traveller the Tenth Doctor (David Tennant) meet while separately investigating Adipose Industries, a company that has created a revolutionary diet pill. Together, they attempt to stop the death of thousands of people in London after the head of the company, the alien Miss Foster (Sarah Lancashire), creates short white aliens made from human body fat. The episode's alien creatures, the Adipose, were created using the software MASSIVE, commonly used for crowd sequences in fantasy and science fiction films.

"Partners in Crime" features the return of three recurring characters: Jacqueline King reprises her role as Sylvia Noble from "The Runaway Bride"; Bernard Cribbins reprises his role as Wilfred Mott from "Voyage of the Damned", to replace the character of Geoff Noble after actor Howard Attfield died; and Billie Piper briefly reprises her role as Rose Tyler for the first time since the second series' finale "Doomsday" (2006), in a scene that was not included in preview showings.

The episode received many positive reviews. Most critics liked the visual effects used to create the Adipose. Critics also praised Tate's subdued acting in comparison to "The Runaway Bride"; Donna was changed from a "shouting fishwife" to a more emotional person when she became a full-time companion. Critics' opinions were split over the episode's plot: opinion on executive producer Russell T Davies' writing ranged from "pure pleasure" to "the back of a fag packet".