Alexander Vlahos (born 30 July 1988) is a Welsh actor best known for playing Philippe, Duke of Orléans, in the Canal+ television series Versailles. In 2012, Vlahos took over from Asa Butterfield in the role of Mordred, for the BBC One drama Merlin.
Vlahos was born in Tumble, Carmarthenshire, before moving to Llantrisant, Mid Glamorgan. He is the son of a Greek father and a Welsh mother, and speaks both Welsh and English. He played ice hockey from ages eight to 18. He trained in acting at the Royal Welsh College of Music & Drama in Cardiff, graduating in 2009.
He first appeared in the BBC Wales drama Crash in 2009, portraying Dylan. The following year, he appeared in the daytime medical soap opera Doctors in a week-long storyline entitled "Master of the Universe," in which he played the lead role of Lewis Cutler. The episodes were then nominated for "Best Single Episode" and "Spectacular Scene of the Year" at the British Soap Awards in 2010. Also in 2010, he appeared in both Pen Talar and The Indian Doctor, and the film Bright Lights.