Mr Kempston and Mr Hardwick were part of a Temparon vessel drawn to 1890s Earth by Professor Elliot Payne's time experiments. The Sixth Doctor claimed that, in a sense, they were the vessel's pilots whereas, in another sense, they were part of the ship itself. They were made of sand and could create duplicates of themselves. They could also make other human simulacra (like Abigail Woburn) and "incomplete" ones (the Sandmen). While in England, they posed as solicitors. (AUDIO: Jago in Love, The Hourglass Killers) He trapped Henry Gordon Jago and George Litefoot in a time loop in order to attact the Sixth Doctor's attention. (AUDIO: The Lonelty Clock)
Unlike the Time Lords, the Temparons lacked true time travel, and sought to absorb the artron energy from the TARDIS in order to access the Time Vortex. They were defeated when the roof of the tunnel which they had built underneath the River Thames collapsed under the weight of the water, causing the two of them, their various duplicates and all of the other Sandmen to be diluted. (AUDIO: The Hourglass Killers)
