Professor Bernice Summerfield and the Secret of Cassandra (audio story)

Professor Bernice Summerfield and the Secret of Cassandra, or simply The Secret of Cassandra, was the seventh Bernice Summerfield audio story produced by Big Finish Productions. It was also the first original audio story produced for the series. This was writer David Bailey's first contribution to a Doctor Who universe story; he continued on to contribute to a range of Doctor Who elements including further Bernice Summerfield stories and Doctor Who Magazine and Doctor Who novels.

For the entire guest cast, this is their only Bernice Summerfield audio story; they have all however appeared in other Big Finish audio story productions.

Publisher's summary
A vicious war between two nations is coming to a head, and the final movements are centred on the sailing ship Cassandra. Along with a very strange cargo, Cassandra carries Captain Colley, a man with his own sad burden, and the paranoid General Brennan, a woman convinced that her actions will end the war once and for all. Their grim mission goes entirely to plan, until the Cassandra gains an extra passenger - a shipwrecked archaeology professor by the name of Bernice Summerfield.

Sensing something is very wrong aboard the ship, Bernice's snooping brings her close to a terrible truth. Soon, Bernice doesn't know who to trust, and she can no longer be sure if anyone is who they claim to be...

Plot
Whilst holidaying on the Earth colony Chosan, Benny falls asleep on her yacht, which drifts into the path of a warship and is destroyed. She washes up on a small island and, after two days, rescued by Captain Colley and brought aboard the automated sailing ship Cassandra, although General Brennan is happy to leave her to die. When she wakes up, Colley gives her a communicator and explains that he is ferrying Brennan to Calabraxia, a country at war with Pevana.

Benny learns that Colley is secretly working for both sides of the war and, in the morning, is attacked by Brennan and taken to the cargo hold where she meets Sheen, Brennan's prisoner. Colley is informed of this by Cassandra's computer and has her released, telling Benny that the war will be over once Sheen arrives in Calabraxia. He explains that his daughter, Cassandra, programmed the ship's systems before joining the Pevanan military's neurotechnology division and disappearing in an attack on Glory Hill. Her loss drove his wife, Nadia, into an early grave and he now wishes to end the war at any cost.

Benny secretly contacts a nearby Pevanan ship and rescues Sheen from his cage with the help of Cassandra and one of her laser guns. He is initially hesitant to leave his cage and, when Benny takes him onto the deck, he powers up a staser cannon and destroys his people's ship despite Benny's protestations. Brennan suffers another headache and tells Benny that she has been working undercover as a scientist at Glory Hill since the Calabraxian attack and that Sheen was the head of a project which sought to create a superweapon. She captured him and is taking him for interrogation, but Benny believes that he and Colley are in league.

Colley returns Sheen to the cargo hold at his request and Brennan searches Colley's room, finding a photograph of his family and realising that he knew Cassandra as one of the scientists who died at Glory Hill. She then has another headache and Benny realises that they happen whenever she thinks about Sheen. As Cassandra destroyed the lock for Sheen's cage, Colley instead takes him to the bridge for the remainder of the journey and asks him to promise that he will destroy Calabraxia, although he is unwilling to watch him do it. Benny arrives on the bridge and Sheen reveals that he is the superweapon.

Cassandra blocks Brennan's memories, allowing her to confront Sheen without suffering a headache. Benny learns that Colley wants revenge for his daughter's death, intending to die with the Calabraxians, and refuses to allow him to use his rescue of her as a way to absolve himself. Sheen then reveals that he is Cassandra, downloaded into a colleague's body before the attack on Glory Hill and willingly experimented on to become a living bomb, and has the ship's computer confirm it. Colley is disgusted by his daughter and kills her, causing the bomb to begin its countdown. To stop it, Benny suggests that Cassandra enters Sheen's body.

After arriving at Calabraxia, Brennan apologises to Benny and departs. Colley intends to sail away from the war with Cassandra for now, realising that he does not want revenge. He thanks Benny and she goes to have some "well-chosen words" with her travel agent after the holiday that she has had.

Cast

 * Bernice Summerfield - Lisa Bowerman
 * Captain Damien Colley - Lennox Greaves
 * General Hannah Brennan - Sally Faulkner
 * Computer - Helen Goldwyn
 * Sheen - Robert Curbishley

Crew

 * Cover Art - Carolyn Edwards (first edition) and Adrian Salmon (second edition)
 * Producer & Director - Gary Russell
 * Executive Producer - Jason Haigh-Ellery
 * Music & Sound Designer - Toby Richards and Emily Baker
 * Writer - David Bailey

Worldbuilding

 * Benny says that she is a vegetarian.
 * Benny's diary is "soundly fritzed".
 * Benny says that she is dying for a gin.

Continuity

 * Bernice returns to Chosan in AUDIO: The Poison Seas.