Brigadier Lethbridge-Stewart

Sir Alistair Gordon Lethbridge-Stewart, generally referred to simply as the Brigadier, is a fictional character in the British science fiction television series Doctor Who, created by writers Mervyn Haisman and Henry Lincoln and played by Nicholas Courtney. He is one of the founders of UNIT (United Nations Intelligence Taskforce, later Unified Intelligence Taskforce), an international organisation that defends Earth from alien threats, and serves as commander of the British contingent. Presented at first as reluctant to accept the continuing aid of the Doctor, over time the Brigadier became one of the Doctor's greatest friends and his principal ally in defending Earth.

As one of the series' most prominent recurring characters over its history, the Brigadier appeared in 23 stories during the original run of Doctor Who, first appearing in the 1968 serial The Web of Fear opposite the Second Doctor (Patrick Troughton). The character made frequent appearances on the series following the introduction of the Third Doctor (Jon Pertwee) in 1970's Spearhead from Space. His final appearance in the program was in 1989's Battlefield opposite the Seventh Doctor (Sylvester McCoy). Nearly 20 years later, Courtney reprised the role in the DVD Special Feature called "Liberty Hall" in 2009 written by Karen Davies and directed by Brendan Sheppard in which the Brigadier was interviewed by a Times journalist. Then he finally appeared in the spin-off programme The Sarah Jane Adventures in 2008, his last appearance prior to Courtney's death in 2011. That year, Doctor Who later paid tribute to Courtney by announcing the Brigadier had died with a line of dialogue in "The Wedding of River Song". Later still, a Cyberman avatar of the Brigadier also appears, and achieves some closure with the Twelfth Doctor (Peter Capaldi), in "Death in Heaven" (2014).