Blackthorne Gasworks was a London-based gas provider. Its exact location was Fentiman's Road, Lambeth. It supplied gas to power the gaslights across the city.When she arrived on Earth, Morjanus installed a proto-morphic lifeform into the building to access the gas system. While it did this, she used self-hypnosis to effectively become Penny Chapman who the went on to work at the factory. She did so for three years until the lifeform was fully integrated.
The Eighth Doctor befriended Penny and detected the unusual technology present in Blackthorne. The two went there and entered through the kitchen door using Penny's key. They found a padlocked door but Penny was able to open it with a touch. Within they found the lifeform. However, with the operation complete, Penny's memories returned. She attacked the Doctor as Pyrodines, created by the lifeform were released outside. Threatening him with a gun, Morjanus forced the Doctor onto the roof of Blackthorne. They conversed and then Morjanus moved to kill him but found the gun empty as the Doctor had pre-emptively emptied it.
Spring-heeled Jack fought with a Pyrodine on the rooftop and Morjanus attacked the Doctor who managed to force her over the edge. She gained a foothold, damaging the brickwork as she did so, and climbed back on top. The Doctor ran and destroyed the lifeform. Jack used his psychic powers to take any memories relating to Morjanus, leaving her as Penny. They then left Blackthorne. (COMIC: The Curious Tale of Spring-Heeled Jack)