Question: The actor that played the title role in the series "Merlin" also appeared in a 2014 2014 British film based on the First World War memoir by what author?
Sentence (from "Colin Morgan"): Colin Morgan (born 1 January, 1986) is a British/Irish film, television, theatre and radio actor best known for playing the title character in the BBC fantasy series "Merlin", the lead in "The Living and the Dead", and main roles in "Humans" and "The Fall"; his stage role as Ariel in "The Tempest"; and film roles in "Testament of Youth", "Legend" and "".
Relevant evidence: Yes