Harrigan Cove Gallagher is a character who originally appeared in the second Canadian Boys movie, Once Upon a Time in Canada. He was later promoted to being a permanent cast member in the main series due to possessing a deep bond with Pictou and his family.
Harrigan Cove is a 33-year-old man of Irish Canadian heritage. He has Vandyke-brown hair, light turquoise eyes and rough stubble growing all over his chin, giving a pleasant exfoliating sensation when he rubs his cheek against someone else's. He wears a ruby-red shirt, bright turquoise trousers fastened with a belt, and grey-and-black shoes with revealing holes in the top. His eyes droop, giving him a permanently tired look. Due to having Irish ancestry, he uses a lot of Hiberno-English terms in his speech, such as "youse" and "craic".
Harrigan Cove has a laid-back and sociable outlook, always loving to relax and chat with friends or family. His amiable disposition has helped forge unbreakable bonds with many people, especially Pictou, whom he has known since his young childhood. He has a great sense of humour (he says that "it's in the Irish genes for us to laugh so much"), and he loves going out on the town at night to meet up with his mates at the pub or tavern to enjoy a ceilidh.
- In Once Upon a Time in Canada, after Harrigan Cove gives his surname as Gallagher, the two-year-old Pictou says he "stays true" to his Irish roots. Gallagher is indeed an Irish surname, originating in present-day County Donegal, Ireland in the 4th century, from the Irish Gaelic for "foreign helper".
- He is one of several characters appearing in Once Upon a Time in Canada who would later become permanent members of the cast of the Canadian Boys series; the others include the Cape Breton fiddling trio (Judique, Campbell and Lime Hill) and Pictou's bullies.