Season 23 of Doctor Who ran between 6 September 1986 and 6 December 1986. It starred Colin Baker as the Sixth Doctor, Nicola Bryant as Peri Brown and Bonnie Langford as Melanie Bush. Though produced as four separate serials from a practical standpoint, it aired as a single, connected serial entitled The Trial of a Time Lord. The season opened with The Mysterious Planet and concluded with The Ultimate Foe.