Shortly before the outbreak of World War II, Dr Brendan Kane qualifies in London as a surgeon. He returns to his native County Donegal, where he hopes to marry and settle down, serving his local community.

Although his country is neutral during the war, the Irish Government agrees to the use of a ‘corridor’ which considerably shortens the flying time for RAF  flying boats operating in the Battle of the Atlantic, thus extending their range and endurance.

After taking off from Lough Erne in Northern Ireland, by following the River Erne for only ten miles, Catalina and Sunderland flying boats of the RAF can reach the Atlantic in minutes instead of a long journey around the coast.

The aircraft do not always return safely  from their patrols and Dr Kane often visits crash sites and tends the wounded  but he also gives medical aid to German U-Boat personnel in distress after being attacked by the flying boats.

Unexpected friendships develop  between the doctor and the men he saves  from both sides of the conflict  and these friendships and deepen as the war draws to a close, some of which will continue long after the hostilities are over.