Charlie Chaplin

Charlie Chaplin was a silent movie star from the early 20th century. After Donna Noble was converted into the so-called "Doctor-Donna", she suggested that she and the Doctor should visit the actor. Moments later, however, she experienced the start of a potentially fatal mental breakdown that forced the Doctor to erase her memories of traveling in the TARDIS. (DW: Journey's End)

The Doctor considered this Donna's "last request". He honored her request by traveling alone to the silent film era of Hollywood to meet Chaplin. Instead, though, he encounterd Archie Maplin, one of Chaplin's competitors. (IDW: Silver Scream)

An earlier incarnation of the Doctor briefly met someone who strongly resembled Chaplin, while trying to prevent the Daleks from obtaining a taranium core vital to their plans of making a Time Destructor. However, the individual was never positively identified, and could have been, like Maplin, a competing actor. (DW: "The Feast of Steven")

Behind the scenes

 * The reference to Chaplin in the Series 4 finale episode marks the second time that a stated desire to meet a famous personage is preempted by the sudden departure of a companion; previously it was the Doctor stating a desire to meet Agatha Christie just before the departure of Martha Jones (DW: Last of the Time Lords); Christie subsequently appeared in The Unicorn and the Wasp.
 * Chaplin's Little Tramp was reportedly one of the influences in determining the style of Patrick Troughton's Second Doctor.
 * Years before playing Jamie McCrimmon, Frazer Hines appeared in Chaplin's film A King in New York, the last film in which Chaplin played a starring role.