Binary (audio drama)

Binary is a Big Finish Productions audiobook based on the long-running British science fiction television series "Doctor Who". The Companion Chronicles "talking books" are each narrated by one of the Doctor's companions and usually feature a second, guest-star voice along with music and sound effects. Unlike most Companion Chronicles releases, this is, for the most part, a full cast audio story.
Plot.
UNIT discovers a lost alien computer which they can't understand how to work. Liz is asked to look it over, instead of the Third Doctor, as they know he wouldn't want them to take advantage of it.
Critical reception.
"Doctor Who Magazine" reviewer Matt Michael said that the audio "works very well indeed".