Director Vic Sarin reported that Connie Nielsen was so immersed into her role that she spent the entire 28-day shoot speaking with an Irish accent, even when off-set.
The actors intentionally speak a very toned down Donegal accent, because international audiences would not understand the much stronger genuine accent spoken by the islanders off the Donegal coast.
Spectacular rainbows and double rainbows are a common occurrence in the part of Ireland where the film was shot.
At his audition John Bell (Tomas) was asked to perform an emotional scene which required him to cry. When he came out of the audition, parents of other young hopefuls took his tears to be real and commented on the stress of the situation, thinking the boy had been put under pressure by ambitious parents.
The monument of standing stones on the island was built for the film. Some of the huge 'stones' were made from concrete, others from polystyrene. However, many tourists to the area mistook the monument for a real stone age site.