Ash Hidminster was a pseudonym employed by actor Sheridan Smith for the audio story The Book of Kells. He was credited with playing "Brother Lucianus".
The pseudonym was an anagram of Smith's name and used to conceal the return of Smith's character, companion Lucie Miller, after her departure from the Eighth Doctor's company in Death in Blackpool, now travelling with the Monk. Her true identity was only made apparent in a post-credits scene with Smith and Lucie making their returns proper in The Resurrection of Mars.