The tide’s mystery is revealed through stories and science from Ireland and around the world. Featuring the world’s highest tides, largest tidal bores and most dramatic whirlpools.

Fishermen on the Xiapu mudflats make an unexpected income from the tide, while at Strangford Lough, Brent geese depend on the tide to eat. And we follow surfer Al Mennie’s tidal training.

A seaweed farm harnesses the strong tides off Rathlin, while in County Down tidal power has a surprisingly long history. And the Arctic tide reveals a story with global reverberations.