In 1999, Big Finish obtained a non-exclusive licence to produce official Doctor Who audio plays.
Though the programme had been put on indefinite hiatus in 1989, the BBC still published, as well as gave non-exclusive licenses to other companies, Doctor Who stories through various mediums such as novels and comics.
[2] Big Finish Productions, which mostly consisted of fans who started out recording fan audio plays, were given the license to record some of the New Adventures, a series of novels from Virgin Books which had originally been licensed Doctor Who stories, into audio plays.
[3][4] This eventually transitioned into a license to produce original audio dramas featuring the past Doctors, with The Sirens of Time being the first story to be released in July 1999.
[8] Since then, every televised companion has reprised their role in Big Finish (with the exception of Jackie Lane's Dodo Chaplet).
[11] The releases have also compared to fanfiction, in the way it tries to "correct percieved transgressions",[12] focus on and deepen the characterisation and emotions of characters,[13] and revitalize the earlier dynamics of some villians[14] while also recontexualising their motivations.[15].
On a more neutral level, they have been characterised as focusing more on the 'interpersonal' than the 'epic'; that instead of homages, they serve as supplements to the story, improving and emphasising other parts of the plot.
[16] Though the BBC has not echoed the sentiment, executive producer Nicholas Briggs considers the audios to be completely canonical.