Andrea Riseborough as Colette McVeigh

Clive Owen as Mac

Gillian Anderson as Kate Fletcher

Aidan Gillen as Gerry

Domhnall Gleeson as Connor

Brid Brennan as Ma

David Wilmot as Kevin Mulville

Stuart Graham as Ian Gilmour

Martin McCann as Brendan

Maria Laird as Young Collette

Barry Barnes as Gerry Senior

Michael McElhatton as Liam Hughes

Gary Lydon as Geoff

Daniel Tatarsky as Watcher

Tom Bennett as Watcher #2

Nicholas Asbury as Agent

Morgan Watkins as MI5 Officer

Karl Shiels as Mulville's Driver / Gunman

Mark Huberman as RUC Officer at Hospital

Ronnie McCann as RUC Constable

Eoin Murtagh as Louie, Fletcher's Son

Alan Devine as Social Club Barman

Ben Smyth as Sean

Nia Gwynne as Female Watcher

Cathal Maguire as Mark

Ian Patterson as News Reporter

Alan O'Neill as RUC Officer

David Herlihy as Senior Staff Officer

Frank Smith as Henderson

Kate Nic Chonaonaigh as Henderson's Wife

Lisa Walsh as Brendan's Girlfriend

Una Carroll as Brendan's Mum

James Greene as British Soldier (uncredited)

Anna Elizabeth McGrath as Mourner (uncredited)