This is an audio trailer, as made publicly available at http://www.bigfinish.com or the site of another distributor. It is provided in an unaltered fashion, save for a slight change in the filename, and the conversion of the native .mp3 format to .ogg, as is required by the software underpinning this wiki.
Copyright for it is likely ultimately owned by BBC Worldwide through licenses extended to the production company. Repurposing or alteration of this file may constitute copyright infringement.