Calshot lifeboat station on the south coast of England gets a call out to one of the biggest jobs its crews have ever faced - an 180-metre-long, 50,000-tonne cargo ship has hit a sandbank and is listing over at a dangerous angle. In their small inshore lifeboats, dwarfed by the huge cargo ship, the volunteers must try to rescue the stricken ship's crew. At Thurso, the most northerly lifeboat station on the British mainland, the crew are called out to investigate a personal locator beacon which has been set off on a remote stretch of rocky coastline. A PLB, a small handheld positioning device used by seafarers, is only set off as a last resort when life is in imminent danger. Meanwhile, on the south coast of Ireland, the crew from Kinsale lifeboat station also face a life-and-death struggle - but this time it is not a person in trouble but a horse that is in danger of drowning in the fast-flowing tidal waters of the River Bandon. Show less