A difficulty in obtaining information about the natural behaviour of wild animals is that detailed observations of the activities of different individuals is necessary over long periods of time, and this is especially hard to achieve with sharks.

The wreck, which has been confirmed to be that of 300-year-old frigate Huis te Warmelo was found at a depth of 64 metres near Helsinki. The vessel was once part of the Dutch navy, specifically a region known as West Frisia. The ship was identified on the basis of hull dimensions, location, structure and armament.

The film - which took five years to make - discovers a superb conservation success story, where sharks are considered sacred.