Career

McGrath was raised in Ashford, County Wicklow, Ireland. She studied the International Baccalaureate at St. Andrews College before graduating from Trinity College, Dublin with a degree in history. She wanted to work in fashion journalism and took a job at Image magazine, before becoming a wardrobe assistant on the set of The Tudors. While working on The Tudors, McGrath was advised to try acting, so she sent photographs around to Irish agents. She said:

Being an actress was kind of like when you’re a kid, and you want to run away and join the circus, it's something you really want to do, but then you grew up and got a proper job. It was a dream, but I didn’t think it would ever be reality, and yet here I am!

McGrath was cast in Damage, an Irish TV-movie in 2007. She also starred in Bedrock Productions's play La Marea at the Dublin Theatre Festival 2007. She appeared in the feature films Eden and Freakdog in 2008, before being cast in Merlin.

In 2009, McGrath starred in a five-part docudrama for Channel 4 exploring the life of Queen Elizabeth II, The Queen, in which she played a young Princess Margaret. Emilia Fox portrayed Elizabeth II in the same episode McGrath acted in, the two had previously worked together as sisters Morgause and Morgana in Merlin. In 2010, McGrath was cast in Madonna's directorial debut W.E., an Edward VIII biopic. McGrath played Lady Furness, the king's former mistress who introduces him to Wallis Simpson.

In February 2011, McGrath began filming the comedy-drama film A Princess for Christmas in Romania. The film premiered in December 2011. In September 2011, McGrath voice-acted the lead character in the Irish animated short film Tríd an Stoirm (Through the Storm). Later that month, McGrath was cast as Oriane Congost in Labyrinth.

In February 2013, McGrath was reunited with her The Tudors co-star and close friend Jonathan Rhys Meyers (McGrath worked in the wardrobe department and portrayed a small role on The Tudors) in NBC and Sky Living's horror drama TV series Dracula, which started airing in autumn 2013. McGrath portrays Lucy Westenra. In June 2013, McGrath co-starred in episode four of the Channel 4 show Dates alongside Gemma Chan as a young lesbian on the dating scene. In 2015, McGrath had a supporting role as Zara in the film Jurassic World. Earlier that year, she starred in the Crackle original spy-thriller, The Throwaways.

In November 2014, McGrath co-starred in a Hozier music video for the song From Eden with the singer. She will co-star in Guy Ritchie's Knights of the Roundtable: King Arthur which will be released in 2017. Katie is the lead actress in Chiller’s original series Slasher which premiered on March 4, 2016. In December 2016 her movie “Buttons” in which she plays one of the main characters will premiere on PBS.

Filmography

Film

Year	Title	Role	Notes
2007	Pebble	Tara	Short film
2011	W.E.	Lady Thelma Furness
2012	Tríd an Stoirm	Alice/Banshee (voice)	Short film
2014	Leading Lady	Jodi Rutherford
2015	Jurassic World	Zara Young
2015	The Throwaways	Gloria Miller
2017	Knights of the Roundtable: King Arthur	Elsa

Television

Year	Title	Role	Notes
2007	Damage	Rachel	TV movie
2008	Eden	Trisha
2008	Tudors, TheThe Tudors	Bess	Season 2, episode 5: "His Majesty's Pleasure"
2008	Freakdog	Harriet Chambers
2008	Roaring Twenties, TheThe Roaring Twenties	Vixen	TV miniseries
2008-12	Merlin	Morgana Pendragon	Main role, 65 episodes
2009	Queen, TheThe Queen	Princess Margaret	Season 1, episode 1: "Margaret"
2011	Princess for Christmas, AA Princess for Christmas	Jules Daly	TV movie
2012	Labyrinth	Oriane Congost	TV miniseries
2013	Dates	Kate Foster	TV series
2013	Dracula	Lucy Westenra	Main role, 10 episodes
2016	Slasher	Sarah Bennett	Lead role
2016	Buttons	Unknown Role

[ Source: Wikipedia ]