The SS Madame De Pompadour was a space ship which was built on 51st Century Earth. It had a crew of 50 and a similar number of Repair Robots, which were designed to repair the ship at any cost to themselves or the crew.
When it was 37 years old the ship malfunctioned in the Dagmar Cluster and the robots did not have the equipment needed to repair the damage. They killed the crew and used their body parts to repair the spacecraft. The last part needed to make the ship fully operational was a Shipboard computer and the robots figured that only the brain of Madame de Pompadour would work. The robots disguised their mechanical nature with 18th Century costumes and modified the ship's engines to rip a hole through Time to France, several thousand years ago. (DW: The Girl in the Fireplace)