Setting off from Plymouth with a plan to make it all the way to the Isles of Scilly, the three men are hampered by the fact that Rory is in charge of getting the boat, a subject he unfortunately knows nothing about. When their first vessel nearly kills them they are forced to beg, borrow and steal boats for the rest of the journey. En route they manage to crash into one harbour, charm their way on board a round the world racing yacht, do their bit for lobster repopulation, lend their voices to an amateur production of Pirates of Penzance and, true to form, indulge their competitive spirit (with a little help from an Olympic gold medal winner).

Dara has a breakthrough hitching a lift on a tug and finally learns to respect the power of the sea. Meanwhile, back on dry land Griff explores Redruth's only working tin mine, and Cornish pride comes to the fore when Rory pays a visit to the place of his birth (now heavily patrolled by police at night). But as the winds pick up and the voyage nears its close, will the boys be able to find a boat willing and able to take them through a force eight gale, the Scilly Isles and their final destination - the spectacular Bishop Rock lighthouse?