The sixth series of British science fiction television programme Doctor Who was shown in two parts. The first seven episodes were broadcast from April to June 2011, beginning with "The Impossible Astronaut" and ending with mid-series finale "A Good Man Goes to War". The final six episodes aired from August to October, beginning with "Let's Kill Hitler" and ending with "The Wedding of River Song". The main series was preceded by "A Christmas Carol", the 2010 Christmas special. The series was led by head writer and executive producer Steven Moffat, alongside executive producers Beth Willis and Piers Wenger. Sanne Wohlenberg, Marcus Wilson, and Denise Paul served as producers. The series was the sixth to air following the programme's revival in 2005 after the classic era aired between 1963 and 1989, and is the thirty-second season overall. The series stars Matt Smith as the eleventh incarnation of the Doctor, an alien Time Lord who travels through time and space in his TARDIS, a spacecraft whose exterior resembles a British police box. It also stars Karen Gillan and Arthur Darvill as his companions, newlyweds Amy Pond and Rory Williams. Alex Kingston also returns as River Song, a mysterious woman from the Doctor's future who is revealed throughout the series to be Amy and Rory's part-Time Lord daughter and the Doctor's wife. In addition to Song, the series continues story threads from the fifth series, most notably the Silence, the cause of the TARDIS exploding in "The Pandorica Opens" / "The Big Bang". Episodes This series was the first to include a mid-season broadcast break since Season 18, with twelve weeks between the transmissions of "A Good Man Goes to War" and "Let's Kill Hitler". Supplemental episodes Two three-minute mini-episodes titled "Space" and "Time", directed by Richard Senior, were released on 18 March 2011, filmed under the sixth series' production cycle as part of BBC One's Red Nose Day telethon for the charity Comic Relief. The episodes form a two-part story, set entirely within the TARDIS, starring Matt Smith as the Doctor, Karen Gillan as Amy Pond and Arthur Darvill as Rory Williams, and were written by the programme's head writer Steven Moffat. Prequels A number of short prequel videos were released online prior to selected episodes' airings. Casting Matt Smith, Karen Gillan and Arthur Darvill continued their roles as the Doctor, Amy Pond, and Rory Williams. Darvill had appeared in the previous