Born in Liverpool, Elisabeth Sladen trained at drama school before joining the Liverpool Playhouse, first as an assistant stage manager and then as an actor. Weekly touring rep, radio and television followed, with early roles in Coronation Street, Z-Cars, Doomwatch and Some Mothers Do 'Ave 'Em, and she worked for two seasons with Alan Ayckbourn's company in Scarborough. She joined Doctor Who in 1973, playing the independently-minded journalist Sarah Jane Smith, and quickly became one of the series' most popular companions. On leaving the programme in 1977, Elisabeth made a return to theatre before appearing in the sitcom Take My Wife and the BBC classic serials Gulliver in Lilliput and Alice in Wonderland; she also presented the children's series Stepping Stones. She reprised the role of Sarah Jane a number of times, on television in K9 and Company and The Five Doctors, and on BBC Radio in The Paradise of Death and The Ghosts of N-Space. In 2006 Elisabeth returned as Sarah Jane for the BBC One Doctor Who episode 'School Reunion'. This led to the spin-off programme The Sarah Jane Adventures, of which five series were broadcast from 2007 to 2011. Elisabeth Sladen died in 2011, aged 63.
Nicholas Courtney was born in Egypt, the son of a diplomat. He grew up in a variety of countries, including Kenya and France, and at the age of eighteen was called up for National Service. Following this he entered the Webber Douglas drama school and trained to be an actor. A stint in repertory theatre was followed by early television roles in programmes including Sword of Honour and Watch the Birdies. His first association with Doctor Who came with the 1965 story The Daleks' Master Plan, in which he played Bret Vyon. In 1967 he returned to the series, making the first of many semi-regular appearances as Colonel (later Brigadier) Alistair Gordon Lethbridge-Stewart. He also appeared on radio alongside Elisabeth Sladen in The Paradise of Death and The Ghosts of N-Space. His other television appearances included Minder, Juliet Bravo, All Creatures Great and Small and Sink or Swim; whilst on stage he appeared in numerous productions including The Dame of Sark, The Rocky Horror Show and The Mousetrap. He also released an autobiography, Five Rounds Rapid! in 1998 and recorded his memoirs (subtitled A Soldier in Time) for a 2002 Big Finish audio CD. Nicholas Courtney died in 2011, aged 81.