 " The Stolen Earth " is the first appearance of the Daleks since " Evolution of the Daleks " , which was filmed eighteen months prior to the episode ; consequently , the prop controllers experienced difficulty re @-@ adapting to their roles . Davies 's inclusion of the Daleks as part of the crossover was intended to create a " charged atmosphere " for the protagonists : Jack was killed by the Daleks ; Rose and Martha were present at two of their apparent extinctions ; and Sarah was present at their creation . The animatronic of the Dalek mutant had to be recreated for the episode , because the previous prop that was used in " Dalek " and " The Parting of the Ways " was irreversibly damaged by water when the latter was filmed . " The Stolen Earth " features two new variants of Daleks : the Supreme Dalek , coloured red as an allusion to the Peter Cushing film Dr. Who and the Daleks ; and the partially destroyed Dalek Caan . Caan was described in the shooting script as : 
