Ned Dennehy is an Irish actor in films and television. His credits include The Mystic Knights of Tir Na Nog (1998), Blitz (2011), Harry Potter and the Deathly Hallows – Part 1, Downhill (2014), Luther, Banished, Dickensian, Peaky Blinders (2017), Versailles, Broken, Outlander, and Shōgun (2024).

Mystic Knights of Tir Na Nog is a fantasy-adventure television series set in a fantasy version of ancient Ireland, created by Saban Entertainment. It was loosely based on actual Irish mythology. The name is derived from Tír na nÓg, one of the Otherworlds of Irish mythology. It was Saban's first fantasy series to involve knights, dragons, and wizards. It aired on the Fox Kids Network from September 12, 1998 to May 7, 1999.