Inspector Gregson was a 19th century officer from Scotland Yard.
In 1892, he congratulated Madame Vastra on cracking a case. He seemed to understand Vastra explaining about her being a Silurian and Strax being a Sontaran, but he seemed somewhat confused afterward. ("Vastra Investigates")
When a dinosaur suddenly appeared in the Thames one day in 1894, Vastra and the Paternoster Gang handed him a sonic lantern to help contain it.
Not much longer after, Vastra sent Gregson and other officers to take care of the Clockwork Droids at the Mancini's Family Restaurant. However, when they went inside and found the droids scattered across the floor, they were too afraid to do anything. Later, in astonishment, they watched as the Half-Face Man's balloon made out of human skin rose out of the restaurant. ("Deep Breath")
