Ruth Matheson

Ruth Matheson was a captain who was in charge of the Vault.

Matheson and Sato were tasked with guarding the Master. This task was unsuccessful, as the Master managed to trick the duo and escaped in his TARDIS. (AUDIO: Mastermind)

Behind the scenes

 * Both Charlie and the Captain have surnames from Torchwood characters. Ruth has Rex Matheson's surname, and Charlie has Toshiko Sato's.
 * Both Daphne Ashbrook and Charlie's actor — Yee Jee Tso — starred in the 1996 TV movie, Yee as Chang Lee, and Daphne as Grace Holloway.