“Secret of Roan Inish” is one of my wife's perennial favorites. She wants to watch it again about once a year if not once every six months or so. I have a lifelong interest in Gaelic culture and folklore, so I'm pretty fond of it myself. It's a gentle, charming little story- almost a kid's movie- but it handles its Gaelic mythological themes with a lot of sympathy and not quite too much whimsy or sentimentality.
Roan Inish means “seal island” in Irish, and the island of the title is inhabited only by seals, since the West Irish people who once lived there have now relocated to the mainland. When they left the island several years before, they accidentally left behind a baby boy, and local legend has it that he is still with the seals, “the other side of the family” as they say.
There are actually certain families in the Gaelic areas of Ireland and the Hebrides who were traditionally said to be descended from seals. Such families usually observed a taboo on eating seal flesh, unlike the other inhabitants of those areas. This and other aspects of the folklore in the movie are generally accurate, which is certainly a nice touch considering how rare it is for a movie to get that sort of thing right.
The real charm of the story, like any story, is in the stories of the characters, including a little girl named Fiona who makes it her personal mission to bring the lost little boy back from the seals- and to get the family back to the island.