The Companion Chronicles The Companion Chronicles was a Big Finish Productions audio series that ran for eighty monthly releases across eight series between 2007 and 2014 , before relaunching with yearly box set releases thereafter . The general , but not invariable , ambition of the series was to tell stories using the companion s of the first four Doctors . The typical release in the range used just two actors , a musical score , some foley work and sound design — meaning that the end result sat somewhere between an audio book and a full - cast drama . Overview . Concept . Originally , the concept was to produce talking books featuring the companions of the first four incarnations of the Doctor who were unavailable to take part in the main range . While the range has remained primarily focused on companions who appeared earlier than Season 19 , most releases in the range have not been true " talking books " . In fact , all but one release — " The Stealers from Saiph " — use the convention of at least two characters in conversation with each other . Most have a sound design worthy of any title in the main range . On rare occasions , the range has moved away from its titular concern and featured characters who are more commonly considered " prominent guest stars " or " allies " , such as King Peladon and Henry Gordon Jago . Format and structure . In general , " Companion Chronicles " have a fairly standard format . They are usually two , approximately 25 minute long episodes divided by a single cliffhanger , barring special double length releases released regularly each season from the fourth onwards . The part of the story that has to do with the Doctor is almost always told in flashback , as a recollection of a past adventure . Thus , the central character of the piece ( i . e . , the companion ) is often depicted in two time periods . That is , there is typically an " older " version of the companion who recounts the adventure with the Doctor , and the " younger " version of the character , who is as he or she appeared on television . The actor not portraying a companion is used in a variety of ways to allow stories in the range to have markedly different structures . Some common narrative uses for the second actor are : Sometimes , the interrogator is " revealed " to be the principal adversary , as in " Mother Russia " or " Frostfire " ; sometimes the listener knows the interrogator is the adversary right from the start , as with " The Catalyst " . In any case , the relationship between ex - companion and interrogator is usually a pretty obvious " framing device " , which takes up a clear minority of the runtime of the release . However , in a few rare cases , as with the " Home Truths " trilogy , the interrogator is a co - star equal with the featured character and is given a a proper story with the " present day " companion woven into the companion ' s recollections of the Doctor ' s TARDIS . The 2011 release " Tales from the Vault " was a departure from the " enhanced audiobook " format , being effectively a straight audio drama ( albeit still one with a limited cast ) that incorporated interviews with various companions . Continuity . A few of the plays tie in to others in the Big Finish Doctor Who range . " The Darkening Eye " is a prequel to " The Death Collectors " ; " Night ' s Black Agents " explicitly occurs between " City of Spires " and " The Wreck of the Titan " ; the Leela trilogy which begins with " The Catalyst " relies to some degree on the listener ' s knowledge of the Gallifrey audio series ; and " The Prisoner ' s Dilemma " occupies a complicated narrative space , tying together the Virgin New Adventures with Big Finish ' s " Key 2 Time " series . All the plays add to the their main characters ' televised continuities . Some detail an adventure that adds little to their lives ; for instance , " Mother Russia " gives Steven an adventure in Napoleonic Russia between the main narrative of " The Gunfighters " and its conclusory scenes , which lead into " The Savages " . Even the interchange with his interrogator is set within the main story . Thus , Steven gains merely another adventure that fits neatly in his established , televised timeline . By contrast , other plays expand greatly on the known fates of their principal character / s . For instance , the trilogy of stories featuring Sara Kingdom , the main narratives of which take place between episodes of " The Daleks ' Master Plan " , reveals that she had other adventures with Steven and the Doctor besides the quest for taranium which was the central plot of her televised adventure . More significantly , the trilogy also gives Sara , or at least her consciousness , a thousand - year - lifespan , a way to have met a different incarnation of the Doctor and thus a second chance to travel in the TARDIS . Most plays settle somewhere between these two extremes . Thanks in part to the typical interrogative " framing device " , most of the plays reveal something about the lives of the Doctor ' s companions after leaving him . In the very first Companion Chronicle , for instance , Vicki is shown to have remained with Troilus and to have had a large family . Equally , the series shows that Susan Foreman stayed with David Campbell , Jo Jones continued her globe - trotting life with Dr . Clifford Jones and Victoria settled down to raise a family .