Yvonne Hartman supplied Jack Harkness, St John Colchester, Ng and Norton Folgate with a submersible for the Sorvix power plant mission. Its controls were similar to a D7.
Yvonne claimed that it had belonged to Torchwood One and was being repaired at Purfleet during the Battle of Canary Wharf, sitting in a government storage hold until she received an invoice for it and learnt of its existence. Mr Colchester came to doubt that this was true, believing that it was far too convenient. (AUDIO: Eye of the Storm)