Anthony Boyle

as Arthur Guinness

Louis Partridge

as Edward Guinness

Emily Fairn

as Anne Plunket

James Norton

as Sean Rafferty

Michael McElhatton

as John Potter

Niamh McCormack

as Ellen Cochrane

Fionn O'Shea

as Benjamin Guinness

Dervla Kirwan

as Aunt Agnes Guinness

Jack Gleeson

as Byron Hedges

Danielle Galligan

as Olivia Hedges