Brendan Gleeson as Father James Lavelle

Chris O'Dowd as Jack Brennan

Kelly Reilly as Fiona Lavelle

Aidan Gillen as Dr. Frank Harte

Dylan Moran as Michael Fitzgerald

Isaach de Bankolé as Simon

M. Emmet Walsh as The Writer

Marie-Josée Croze as Teresa

Domhnall Gleeson as Freddie Joyce

David Wilmot as Father Leary

Pat Shortt as Brendan Lynch

Gary Lydon as Inspector Stanton

Killian Scott as Milo Herlihy

Orla O'Rourke as Veronica Brennan

Owen Sharpe as Leo

David McSavage as Bishop Garret Montgomery

Mícheál Óg Lane as Mícheál

Mark O'Halloran as Prison Officer

Declan Conlon as Father

Anabel Sweeney as Girl

David Pearse as Father