Walter, a young boy with physical and mental disabilities, walks with his mother to a local railway bridge to watch steam trains pass by. Unnoticed by Walter, however, his mother leaves him unattended on top of the bridge. Later, she turns back, hoping to find her disabled son has fallen to his death. Discovering he has not, she rushes back to sweep him up in her arms.

Some years pass. Now a young man, Walter is subjected to teasing, bullying and impatience from his packing factory co-workers, and given little support from his silent and distant father. In the workplace he is tolerated, even liked by some, but when he becomes confused and angry, ripping a box to pieces, a crowd of colleagues try to calm him by asking what he'll watch on television that evening, to which he responds by parodying a sports programme. His excitement and the crowd's baying response create such noise that the warehouse supervisor yells for silence.

Walter develops a strong bond with his father's pigeons. After his father's death he spends more and more time tending to their needs. His mother responds to her husband's death by continuing her routine of care for Walter - this amounts to brusque exchanges and expounding her heartfelt belief that their lives have been a kind of punishment.

Some days later Walter wakes and calls out for his mother. There is no reply. He runs downstairs to check the calendar. He returns upstairs and finds his mother in her bed. She has died in her sleep. He fetches a pan of water and pours it onto her face; eventually he realises she will not be waking up again.

Now orphaned, Walter is placed in a barely functional institution and surrounded by often highly disturbed patients. On his first night in the ward he is sexually molested; the cries and screams of the other inmates continue long afterwards, creating an eerie chorus which eventually lulls him to sleep.

The nursing staff quickly make use of Walter, realising he is more capable than the other inmates. Nonetheless he seems isolated and out of place in such an extreme environment. As he falls asleep he remembers his father's pigeons, which have become a symbol of freedom for him.

Christmas arrives and, as the local children's choir sings carols, Walter talks to Joseph, one of the nurses, of his hopes to have a baby. Joseph is sympathetic but discouraging, admitting that Walter doesn't deserve his current fate. Walter returns to his seat, to endure the first of many institutionalised Christmases.