Secret Heart

The Secret Heart was one of the last Racnoss spacecrafts after the war between the Racnoss Empire and the Fledgling Empires. It was similar in design to the Empress of the Racnoss' ship, the Webstar, and was also powered by Huon energy.

Roughly 4.6 billion years ago, the Secret Heart escaped from the Empires. It entered the Sol system and became trapped inside the Earth as the planet was formed, attracting rocks to it and trapping itself. In 2007, Huon energy created by Torchwood woke the Secret Heart's crew, but the escaping Racnoss were drowned when the Tenth Doctor blew a hole in the underground chamber and the River Thames was drained, its water cascading onto the crew. (DW: The Runaway Bride)