As storm Ophelia hits the British Isles, on the south-east coast of Ireland the Rosslare crew try to rescue a small yacht with three people on board. In Devon, the crew at Appledore race an incoming tide to try and reach a man stuck fast in quicksand, while on the north coast of Cornwall the crew of St Agnes must battle through huge breaking waves to reach two young boys being swept out to sea in a deadly rip current.