Silver Lining (audio story)

Silver Lining was a special Big Finish recording featuring Bernice Summerfield encountering the Cybermen. The recording was given away with Doctor Who Magazine #351.

Publisher's summary
The Planet Tysir IV:

Benny Summerfield, archaeologist, adventurer and all-round trouble-magnet is asked to investigate the remains of an ancient civilisation. As she digs deeper into the mystery, Benny discovers that Tysir IV is not quite as dead as she'd been told...

Plot
Benny accepts an invitation to the Earth colony Tysir IV from historian Lynton Jellis, a fan of hers who wants her to confirm or refute that the planet was home to recent indigenous life and thus discover whether or not the colony is legal. Upon arrival, she signs Lynton's copies of Down Among the Dead Men and the rest of her works and travels with him to the site where giant robot miners have discovered a metallic doorway which seems familiar to her. She solves a musical puzzle and opens it.

Inside, Benny realises that it is a base belonging to the Cybermen. They climb down a hatch to a control room where Lynton draws a gun and reveals that he has used Benny to acquire a plague for the United Polon Independence Party, having learnt of it after hacking into the cyber computer. He sets explosives and leaves her with a Cyberman whom she convinces to work with her to escape. They climb through the ventilation shaft and find that Lynton has been killed by the plague, which the Cyberman explains was intended to infect the planet's inhabitants and force them to be converted to save themselves.

The Cyberman pulls the door open and Benny slips through before using Lynton's gun to destroy the opening mechanism and cause them to crush the Cyberman. She is unable to get clear of the base before it explodes and is wounded, later finding herself at Medic Station Alpha where she sends a message to Braxiatel letting him, Jason and Adrian know why she is yet to return to the Collection. She admits that she feels guilty about betraying the Cyberman.

Cast

 * Bernice Summerfield - Lisa Bowerman
 * Lynton Jellis / Cybermen - Nicholas Briggs

Continuity

 * The Cybermen's base contains an intelligence test similar to one found on Telos. (TV: The Tomb of the Cybermen)