Question: In what drama did the Saving Mr Banks and Saul Dibb's 2015 WW2 romance actress portray Alice Morgan?

Context paragraphs:
Catherine Johnson (novelist): Catherine Johnson (born 1962) is a British author and screenwriter.  She has written several young adult novels and co-wrote the screenplay for the 2004 drama film "Bullet Boy" (directed by and co-written with Saul Dibb).

Journey's End (2017 film): Journey's End is a British film adaptation of the play "Journey's End" by R. C. Sherriff.  Written by Simon Reade and directed by Saul Dibb, this is the fifth film adaptation of the play, following "Journey's End" (1930), "The Other Side" (1931), "Aces High" (1976) and a 1988 BBC TV film.  The film was screened in the Special Presentations section at the 2017 Toronto International Film Festival.

Ruth Wilson: Ruth Wilson (born 13 January 1982) is an English actress.  She is known for her performances in "Suburban Shootout" (2005), "Jane Eyre" (2006), and as Alice Morgan in the BBC TV psychological crime drama "Luther" since 2010.  Her film credits include: "Anna Karenina" (2012), "The Lone Ranger" (2013), "Saving Mr. Banks" (2013), "Suite Française" (2015), "Locke", and "I Am the Pretty Thing That Lives in the House" (2016).  In 2014, she began starring in the Showtime series "The Affair".

Bullet Boy: Bullet Boy is a 2004 British drama film directed by Saul Dibb, written by Saul Dibb and Catherine Johnson, and stars Ashley Walters.  The film’s original music was composed and performed by Robert Del Naja of Massive Attack, who released it as an album.  The film is about a family in crime-ridden east London, the eldest son’s involvement in gun crime, and the effects of this on his younger brother.

Mike Dibb: Mike Dibb (born Leeds, West Yorkshire, 29 April 1940) is an award-winning English documentary filmmaker.  In almost half a century of making films mainly for television – on subjects including cinema, literature, art, jazz, sport and popular culture – "he has defined and re-defined not only the televisual art documentary genre but has been able to make moving image pieces as a form of self portraiture".  Dibb has made many acclaimed films, including on Federico García Lorca, C. L. R. James, Astor Piazzolla, Miles Davis, Keith Jarrett, Barbara Thompson and other notable subjects.  In the words of Sukhdev Sandhu in "The Guardian": "In a career spanning almost five decades, it's possible Dibb has shaped more ideas and offered more ways of seeing than any other TV documentarian of his generation."  Mike Dibb is the father of film director Saul Dibb.

Ruth Caleb: Ruth Irene Caleb OBE, was born in 1942, and is an award-winning veteran film and television producer.  She was appointed head of drama at BBC Wales in the mid-1980s, making her the BBC's first ever female head of drama.  She is known for her work on productions that include; Pawel Pawlikowski's Last Resort, the BBC1 series Judge John Deed and Saul Dibb's Bullet Boy.

Saul Dibb: Saul Dibb (born 1968) is an English director and screenwriter.  His father is the documentary maker Mike Dibb.

The Duchess (film): The Duchess is a 2008 British drama film directed by Saul Dibb.  It is based on Amanda Foreman's biography of the 18th-century English aristocrat Georgiana Cavendish, Duchess of Devonshire.  It was released in September 2008 in the United Kingdom.  The film received the Academy Award for Best Costume Design at the 81st ceremony in 2009.  Costumer = Michael O'Connor

Suite Française (film): Suite Française is a 2015 British-French-Belgian romantic World War II drama film directed by Saul Dibb and co-written with Matt Charman.  It is based on the second part of Irène Némirovsky's 2004 novel of the same name.  The film stars Michelle Williams, Kristin Scott Thomas, Matthias Schoenaerts, Sam Riley, Ruth Wilson, Lambert Wilson and Margot Robbie.  It concerns a romance between a French villager and a German soldier during the early years of the German occupation of France.  "Suite Française" was filmed on location in France and Belgium.  It was released theatrically in the UK on 13 March 2015 and will premiere in the US through Lifetime cable network on 22 May 2017.

The Line of Beauty (TV series): The Line of Beauty is a British drama television series that was first broadcast on BBC Two on 17 May 2006.  The three-part series, written by Andrew Davies and directed by Saul Dibb, is an adaptation of the novel "The Line of Beauty" by Alan Hollinghurst.

Supporting paragraphs: Ruth Wilson Suite Française (film)
Answer: Luther