The St Stephen's Day wren "hunt" still occurs all over Ireland, though the real bird has been replaced with a fake one that's paraded through the streets.
The film's producer, Sorcha Bacon, also appears as Guard no.1.
The biggest challenges were creating an authentic Irish winter in the Midlands in May. And finding a prison within budget. But Rutland's tourism officer came to the rescue, and ended up serving as the film's locations manager.