Albert Runcorn was a Ministry of Magic employee of high rank during the administration under Pius Thicknesse. His chief function was an investigator of alleged Muggle-borns. In this capacity, he uncovered the falsified family tree of Dirk Cresswell.
During Pius Thicknesse's administration of the Ministry of Magic, Runcorn informed on Muggle-borns to the Ministry of Magic, subsequently leading to their arrest and imprisonment. In 1997, Harry Potter impersonated Runcorn when he, Hermione Granger, and Ron Weasleyinfiltrated the Ministry. The Polyjuice Potion used to achieve this impersonation was made with Runcorn's hair, obtained in the commotion caused when Runcorn ate a Nosebleed Nougat. The real Runcorn went home with an uncontrollable nosebleed, while Harry became a fake Runcorn and used the disguise to gain access to the Ministry. Once in the ministry Harry disguised as Runcorn helped Mary and Reginald Cattermole escape with their children, with the assistance of Hermione Granger (disguised as Mafalda Hopkirk) and Ron Weasley (disguised as Reginald Cattermole).
PostWar
It is possible after the War that Runcorn was arrested and sent to Azkaban for acompany the Death Eater Rule.
Runcorn was described as more than six feet tall, and powerfully built, with a black beard and a gravelly voice. It was said that he was very intimidating to the likes of Reginald Cattermole.
Relationships
Arthur Weasley: Runcorn and Arthur Weasley worked at the Ministry of Magic together, and did not get along very well. This was due to the fact Mr Weasley did not approve of Runcorn's persecution of Muggle-borns.
Dolores Umbridge: She and Runcorn were work colleagues, working in close proximity with each other during the Second Wizarding War. Although Umbridge was Runcorn's superior, they got along quite well as they had similar opinions concerning Muggle-born witches and wizards.
Behind the scenes
The real Runcorn only appears twice, once when Pius Thicknesse gives a speech in the Atrium, and again before Harry transforms into him using the Polyjuice Potion.
Runcorn is clean shaven in the film, but in the book, Runcorn had a beard.
The outfit which Runcorn wears in the film adaptation of Harry Potter and the Deathly Hallows, is in line with the Nazi imagery of the film. The leather trench coat when combined with Runcorn's duties and demeanour give him the appearance of a Gestapo operative.
