Maria, a novice at a strict Salzburg convent, loves the majestic landscape of the Alps and often forgets about her religious duties and instead goes hiking on the mountains. The Mother Abbess, a very wise woman, thinks Maria might be better suited to life outside of the convent and decides to send her to Captain von Trapp's home to be the governess to his seven children.
When she arrives there, Maria is surprised at the military discipline which their father, a distinguished and widowed naval officer, exercises over his children and discovers that she is the latest in a long line of governesses that the children have driven away. Maria takes a different approach, instead of educating the children she introduces music into their lives. She teaches them how to sing, play and laugh and is rewarded with the children’s sympathy and love.
The children perform a puppet show for their father and this is where we see the blossoming love between the Baron and Maria for the first time. However, just a few days later the Captain presents Baroness Schroeder to his children as his fiancée. During a ball, the Captain and Maria perform a traditional folklore dance for the children and while they are dancing they discover their feelings for one another. Baroness Schroeder encourages Maria to leave the Trapp family home immediately and she flees back to the convent.
The children soon feel the loss of Maria and think about ways to make her come back meanwhile the Captain decides to marry Baroness Schroeder. Back at the convent Maria confesses her love for the Captain and the Mother Abbess makes her climb every mountain for her love. She hurries back to the Trapp family home only to find that the Captain has set his mind to marrying the Baroness. However, the Baroness sees the true love between the Captain and Maria and leaves. Maria marries the man she loves in the abbey where she was a novice accompanied by the seven children.
In a twist of fate, when they return from their honeymoon the Nazis have already seized occupation of Austria. The Captain plans to escape from enforced naval service and sees his opportunity: the whole family is to take part in a choral festival at the Salzburg Festival Hall. This is where the captain sings “Edelweiss”, an expression of his love for his country just hours before he has to leave it forever. The von Trapps make a dramatic escape after hiding out in the cemetery at the abbey.