Corban Yaxley

Corban Yaxley is one of Lord Voldemort's Death-Eaters, who appears as a minor antagonist in Harry Potter and the Half-Blood Prince, a supporting antagonist in Harry Potter and the Deathly Hallows, and the secondary antagonist in the film adaptation Harry Potter and the Deathly Hallows Part 1.

He was portrayed by Peter Mullan.

Role in The Half-Blood Prince
In the sixth Harry Potter book, Yaxley is one of the Death Eaters invading Hogwarts. He is present when Dumbledore is killed and fights in the battle before leaving the castle with his fellow Death Eaters.

Role in Deathly Hallows
Yaxley serves as one of Voldemort's spies inside the Ministry of Magic. He places Pius Thicknesse under the Imperius Curse on Voldemort's orders, so Thicknesse can kill the previous Minister for Magic (Rufus Scrimgeour). Usurping the role of Head of Magical Law Enforcement as well as cursing Minister Thicknesse proved to be the kingpin for Voldemort gaining control of the Ministry of Magic.

Yaxley appears at the table during the Death Eater's meeting held at the Malfoy Manor. He confidently informs Voldemort that he overheard the date of when Harry Potter is going to be moved from Private Drive, the house of his aunt and uncle's.

However, Snape corrects Yaxley that The Order of the Phoenix tricked him by rumouring a false move date, allowing Yaxley to think he'd figured them out.

As Yaxley is the Head of Magical Law Enforcement, he also has a hand in the Muggle-Born Registration Commission, a position he is clearly unashamed of, as he openly threatens Reginald Cattermole's wife, Mary, over a minor disagreement at the Ministry of Magic. We later find him at Mary Cattermole's trial with Dolores Umbridge, the Head of the Muggle-born Registration Commission.

The trial is interrupted, however, when Reginald Cattermole (Ronald Weasley in disguise), Albert Runcorn (Harry Potter in disguise), and Mafalda Hopkins (Hermione Granger) rescue Mary by unleashing Dementors and flee the courtroom. Although Ron does manage to stun Yaxley, he recovers quickly and gives chase. Leaving Mary with her real husband in the atrium, the trio accesses the Floo Network, but not before Yaxley grabs hold of Hermione. She had already begun to apparate to Grimmauld Place and brought him with them.

Realizing the mistake and danger, Hermione quickly disentangles herself from him and takes Ron and Harry to safety, leave Yaxley on the front stoop of 12 Grimmauld Place. He later fights in the Battle of Hogwarts and he's present when Voldemort attacks Harry in the Forbidden Forest. His exact status after the Battle of Hogwarts is unknown, it can be presumed he was either killed in the battle, or later captured and imprisoned under Kingsley's Shacklebolt's de-corrupted Ministry of Magic, along with all other Death Eaters and their allies.

Trivia

 * On the DVD version of Harry Potter and the Deathly Hallows: Part 1, Yaxley is seen in one of the deleted scenes where he enters the Granger's house, only to find it empty (Hermione Obliviated her parents and manipulated their memories to not only remove all traces of herself, but in still the idea that moving to Australia was a life long dream).