The story starts with the Cleary family in New Zealand:the father Paddy,his wife Fee,and the children,the most prominent being the eldest son Frank,and the youngest (and only daughter) Meggie,who becomes one of the two central characters in the story.
They move to Drogheda,where Paddy's sister Mary lives.She hires them to take care of her estate.Mary is the richest person in the area.Ralph,a handsome,ambitious priest stuck in the outback tries to befriend her,to gain her money and to help him advance in the Catholic hierarchy.Ralph takes care of Mary's relatives,and takes a liking to Meggie.
Ralph is the centre of young Meggie's life,and Ralph has never felt so strongly about any other girl.Meggie is happy,with Ralph and her dear brother Frank.However,Frank's relationship with his father Paddy has never been peaceful.In an argument,Paddy blurts out the truth about Frank:Frank is not Paddy's son.Fee,when a young woman,had an affair with a married politician,and the result,Frank,was already eighteen months old when Paddy married her.Fee had always loved and given more attention to Frank than any of her other children.Stunned,Frank runs away to become a boxer.
With Frank gone,Meggie clings to Ralph.Mary dies,and she leaves all her money in the control of Ralph because of a kind of love she had for him.Ralph treats the Cleary family generously.He pays them generously and makes sure that they are well taken care of.He himself gains the attention of the Church,and is promoted to Sydney.
Before he leaves,Meggie confesses her love for him.Ralph refuses her because of his duties as a priest and he entreats Meggie to find and marry a beau.Then he leaves her.Paddy and Stuart die in natural disasters.
Meggie then courts Luke,who has recently come to Drogheda.He looks remarkably like Ralph,and Meggie takes a liking to him.He marries her and takes her away.He works as a sugar cutter,and he leaves Meggie in a poor place to work as a maid.Meggie is lonely and distraught,and she bears a child,Justine.Ralph visits her once during her labour,as she was yelling his name and not Luke's.Ralph wants to say goodbye because he is leaving Australia,but Meggie yells and swears at him.He leaves her again.
Meggie is getting weaker and weaker,and the family she is staying with pities her greatly.They send her to a quiet summer resort for rest.Ralph comes back on a holiday to find Meggie.The family tells him where she is.He joins Meggie,and then a revelation comes over him.He loves Meggie more than God,and he is indeed only a Man,no matter how Godlike he had tried to become.They spend a few days together,and he is forced to return to his position.Meggie leaves Luke,but does not divorce him,because she is now pregnant with Ralph's baby.
She names the child Dane.Fee knows who the father is because of her own experience.Frank is in jail and her heart is in pieces.Meggie's relationship with her mother improves.
As Dane grows up he wants to be a priest.Fee tells Meggie that what she stole from God,she has to give back.Justine wants to be an actress and leaves Australia and seeks her dream.Dane goes to Ralph,who is now a Cardinal,but Ralph does not know that Dane is his own child.He takes great care of him and because of their resemblance,people mistake them for uncle and nephew.Ralph and Dane encourage the rumour,so Ralph's close relationship with Dane is not mistaken for favoritism.
Dane drowns in Greece,whilst a civil war is going on.Meggie needs to find her child.She seeks Ralph's help.He refuses to help right away,but Meggie tells him the truth about Dane.Immediately,they fly together to Greece and bring back Dane's body back to Drogheda.Soon after Dane's death,Ralph passes away.
Justine believes that the death of her brother was her fault.The book ends with her living happily with Rainer,a distinguished German who loved her from the beginning and had the patience to wait for her to recognise that she loved him.
The book's title refers to a kind of bird that searches for thorn trees from the day it is born.When it finds the tree,it pierces its own heart on the thorn,and sings the most beautiful song ever heard on earth as it dies.Pain is the price to pay for the very best.