It is 1845 and eighteen-year-old Liam Reilly has no idea that his world is about to be shattered. He cherishes County Mayo with its beauty and close family even though life is hard. As tenants, the Reilly's crops go to the English landlord while they eat mainly potatoes. Liam still hopes for rights and a better life, especially when he meets the beautiful Colleen at a wedding in nearby Ballinglass. Terror strikes her village when her landlord razes it to the ground to create pasture. Her family is forced to the dreaded workhouse, and thinking he sees her at a high window, Liam prays she can survive. Liam's brother Niall accompanies friends from Ballinglass to England to earn passage to America. When Niall announces he too is emigrating, the devastated family prepares for his "American wake," knowing this goodbye is forever. Turf cutting, harvest, and roof thatching distract Liam until one dawn in August, he hears the door open and Mother's scream. Horrified, he rushes out to plants consumed by fungus. All Ireland's potatoes are ruined and starvation spreads. People gather to write petitions, begging for assistance, but high government officials in London refuse to interfere and send more soldiers to guard convoys taking food to port. Liam and his father risk arrest and organize thousands in a peaceful march to ask their landlord for mercy. Marching home, Liam hears distant shots and recalls his brother Sean's talk of stealing oats from a convoy. Frantic, he realizes he's missing as soldiers search the marchers for a wounded lad.

Trapped in a desperate struggle, the family pulls together with great courage. When Liam kills a swan for Christmas dinner, he longs for Colleen more than ever. The government confiscates their meager goods as tax and pushes the family to the edge. Liam and his brother face constant danger from guards and soldiers as they scavenge for food. Intense conflict and suspense propel the story forward until at the end, Liam must overcome great obstacles if he is to save his mother and sisters. At 10 Downing Street, 1849, government leaders argue while Ireland falls silent.