Greta, married to a Marxist and living in Oxford, has turned her back on her Catholic Belfast background. Suffering post-natal depression, she goes to stay with her sister Helen in London, where she reveals she is experiencing religious visions. When their father suffers a heart attack they are called back to the family home in Belfast and all the old grievances and jealousies are bared. Greta finds herself confronting the identity that she has wilfully excluded for so long.