Retrieval (audio story)

Retrieval was the third story in the audio anthology Assembled, produced by Big Finish Productions. It was written by Guy Adams and featured Jemma Redgrave as Kate Stewart, Ingrid Oliver as Petronella Osgood, James Joyce as Josh Carter and Warren Brown as Sam Bishop.

Publisher's summary
As the Earth's primeval rulers reclaim their birthright, UNIT must stand against them. Kate Stewart and Osgood venture into a Mediterranean stronghold to retrieve a means to fight back.

But a Silurian warrior is on their trail. Once she has the humans' scent, Commander Tryska will never give up the hunt.

Plot
A UNIT ship and its crew are killed by one of Krelix's bioengineered weapons. Trying to find the Silurians' device to control them, Osgood has identified a Silurian nest off the Greek coast as a research base. She and Kate head there and are spotted by Commander Tryska, who reports the threat that they pose to Grand Marshal Jastrok. When Kate and Osgood enter the underwater caves, Tryska attacks the soldiers outside and demands to know their mission.

Believing it to be for detecting Silurian life, Osgood uses a Silurian device which she soon realises is for attracting reptiles. Her second attempt at using a Silurian device proves successful when she uses another as a key for a passage leading deeper into the cave system. Inert Troodon wake up and toy with her and Kate, assessing how much of a threat they are, and Kate contacts Sam after they are trapped in a cave, but they find the way to a hibernation chamber and discover that the inhabitants are dead and rotting.

Tryska enters the nest, kills the Troodon and attacks Kate and Osgood, poisoning the former with her tongue and using a fear trigger that she has recovered to amplify the latter's race memory and make her made with fear. As Tryska chases Osgood, Sam finds Kate and gives her the broad-range antivenom as a temporary measure before going to save Osgood. He damages Tryska's fear device and takes her captive in the hopes that she can cure Kate, tearing off some of her uniform and putting it in her mouth to keep her from poisoning him. He finds Osgood and heads to the weapons lab where Tryska escapes from her handcuffs and attacks, but falls over the edge of a pit and lets go rather than accept Sam's help.

Tryska survives the fall and contacts Jastrok, claiming to have dealt with the humans and suggesting that they self-destruct the nest. He agrees in order to keep the information from the humans.

Kate uploads data on the various Silurian subspecies to the UNIT Cloud and administers an antitoxin in the biochemical lab. She is reunited with Osgood and Sam and decides to collect as much technology as she can, but the self-destruct is activated and they flee. Tryska stands in their way and fights them until Osgood has Sam attach the device that attracts reptiles to her. Snakes surround her as Kate, Osgood and Sam swim to safety and are airlifted to safety by Josh. The research facility explodes.

General Kalana finds Tryska's body and reports back to Jastrok. She recovers the damaged fear trigger and takes it to him, hoping that her sister died well. If she comes across UNIT, she promises that she will avenge her.

Cast

 * Kate Stewart - Jemma Redgrave
 * Osgood - Ingrid Oliver
 * Sam Bishop - Warren Brown
 * Josh Carter - James Joyce
 * Jastrok - Richard Hope
 * Tryska / Kalana - Neve McIntosh

Worldbuilding

 * Kate speaks with the Prime Minister.
 * Kate and Osgood find live Troodon, which Osgood believed would have been extinct before the Silurians got so technologically advanced.
 * Tryska uses a fear trigger.
 * Josh is using the call sign Hawk Four.
 * Sam has several swimming certificates.

Continuity

 * Krelix told Jo that a device was made to control his creations. (AUDIO: Tidal Wave)
 * Osgood mentions the Wenley Moor incident. (TV: Doctor Who and the Silurians)