Question: Which 2016 Irish independent horror film did Catherine Walker star in?

Context paragraphs:
Jim Hemphill: Jim Hemphill (born December 6, 1971) is an American filmmaker and critic.  He began his career writing about film in publications including the Chicago Reader, Film Quarterly and the American Cinematographer magazine.  In 2007 he directed the independent horror film "Bad Reputation", which won multiple awards at film festivals including Shriekfest, The Chicago Horror Film Festival, and the Weekend of Fear in Erlangen, Germany.  In 2012 he directed "The Trouble with the Truth", an award-winning independent film starring Lea Thompson and John Shea.

Noriko's Dinner Table: Noriko's Dinner Table (Japanese: 紀子の食卓 , Hepburn: Noriko no Shokutaku ) is a 2006 Japanese psychological horror film, and a prequel to the independent horror film "Suicide Club"/"Jisatsu Sākuru" (2002), written and directed by Sion Sono.

Vampires vs. Zombies: Vampires vs. Zombies is an independent horror film loosely based upon J. Sheridan Le Fanu's classic 1872 novel "Carmilla".  Unlike Le Fanu's story, however, most of the action in the film takes place inside a car.  The title and the cover were obviously inspired by the horror film "Freddy vs. Jason", it's unclear if it was intended as a mockbuster of that film or not.

The Unkindness of Ravens: The Unkindness of Ravens is a 2016 Scottish horror film that was directed by Lawrie Brewster.  The film stars Jamie Scott Gordon, who previously appeared in Brewster's 2013 debut horror film "Lord of Tears", as a veteran that comes face to face with demonic ravens.  The film had its world premiere on 27 August 2016 at the London FrightFest Film Festival.  Prior to its release the horror website Bloody Disgusting marked "The Unkindness of Ravens" as one of their "10 Must-See Independent Horror Films of 2016".

A Dark Song: A Dark Song is a 2016 Irish independent horror film, written and directed by Liam Gavin and starring Steve Oram and Catherine Walker.  It was released to select theatres and digital streaming platforms on 28 April 2017.  It is Gavin's directorial debut and, although the public reception has been more mixed, it received a largely positive critical response.

Catherine Walker (actor): Catherine Walker (born 1975 in Dublin) is an Irish actress, notable for British and Irish television appearances including "The Clinic" (2003–2009), "Northanger Abbey" (2007), "Bitter Sweet" (2008), "Critical" (2015) and "A Dark Song" (2016).  More recently, she appeared as the character Scarron or Madame de Maintenon in series 2 of the TV series "Versailles".

Unrest (2006 film): Unrest is an independent horror film.  It was shown at the horror film festival 8 Films To Die For during the 2006 fall season.

100 Tears: 100 Tears is an American independent slasher black comedy horror film directed by Marcus Koch and produced by Joe Davison.  It follows the story of a circus clown going on a murderous rampage after being wrongfully accused of rape.  The film stars Georgia Chris, Joe Davison (who also produced the film), Jack Amos, and Raine Brown, and was distributed by Anthum Pictures in 2007.  The film was generally well received by independent horror film critics and has since garnered a cult following.

The 7th Hunt: The 7th Hunt is an independent horror film from Australia, directed by J.D. Cohen, co-directed by Darren K Hawkins for Cinegear Productions/Coherent Productions in 2008 and first screened in 2009.  It is widely considered to be of the Ozploitation (Australian Exploitation) genre.  The plot revolves around a group of sadistic killers and their victims.  The film featured in the New York City Horror Film Festival in 2009, the Grimm Up North Film Festival in the UK, and the Atlanta Horror Film Festival.  The film stars actress and swimsuit model Imogen Bailey of Neighbours fame.

Brentwood Strangler: Brentwood Strangler is a 2015 award-winning holiday-themed horror short film.  It was written and directed by John Fitzpatrick following the success of his first short "Skypemare", and stars 'scream queen' Jordan Ladd and Australian actor Adam J. Yeend in the title role.  The film premiered December 2015 at the A Night of Horror Film Festival in Sydney, Australia, and had its U.S. premiere in early 2016 at the Hollywood Reel Independent Film Festival in Los Angeles where it won the jury award for Best Genre Short.  The film has received critical acclaim from the independent horror community with multiple online reviews citing Fitzpatrick's writing, and the chemistry between the two leads.  The film has screened at multiple festivals and horror conventions around the world including Shriekfest, Horrible Imaginings Film Festival, FilmQuest, and at Phoenix Comicon where it won the audience award for 'Best Horror'.  The producing team went on to make the popular online series "Scary Endings" which is currently in its second season.

Supporting paragraphs: Catherine Walker (actor) A Dark Song
Answer: A Dark Song