Polly Plummer, born in 1889, was raised in London, England in a small home that was part of a row of joined houses. During the summer of 1900, she met and befriended her neighbor, Digory Kirke. One rainy day, they were exploring a back hallway that connected all the houses on their block when they accidentally stumbled into the study of Digory's Uncle Andrew, who tricked Polly into touching one of his yellow rings. Upon touching it she vanished, and seconds later, found herself climbing out of a pool into a wooded area, were time seemed to stand still. A few minutes later, although it seemed like an eternity, Digory emerged from the same pool she had come out of.
The named the wooded area the Wood Between the Worlds, and noted that there were many pools around them. Digory told her that Uncle Andrew had created magic rings that took you to different places, and he had given Digory a green ring that would take them back home.
Before going back, they decided to jump into another pool to see where it went. It took them to another world called Charn, and the children explored the ruins. While there, Digory accidentally awoke Queen Jadis from her enchanted sleep against Polly's wishes and advice. The queen was cruel and they tried to escape back to the Wood alone, but Jadis managed to grab Polly's hair before they could get away and they all went together.
When back in the Wood Between the Worlds, the children were able to free themselves from the Jadis’ clutches and ran to their home pool However, they were not fast enough, and she followed them back into their own world. There, Jadis declared herself empress and began to create a great havoc in the city. Polly and Digory were terrified and tried to think of a way to get her out of their World. This was managed when they were able to get Jadis (and a few unsuspecting passerby's) to come in contact with them when they touched their yellow rings.
They tried to jump back into Jadis' home pool; however, they learned they had picked the wrong one. They found themselves in a great emptiness, that lasted until Lion sung the dark world into existence. After witnessing the creation of Narnia, Digory went up to the Lion named Aslan, who declared that Digory had brought the evil Witch, Jadis, into this pure world of Narnia. The children were given the task to get a magical apple that would grow into a tree that would protect Narnia, and Aslan equipped them with a flying horse that would take them to the apple.
After a few days of journeying, they arrived at a gated garden that had the apple within. Polly waited outside as Digory went in, and was terrified when Jadis followed Digory out. They managed to keep away from her and made it back to Narnia in due time. Digory gave the apple to Aslan, who instructed him to plant it. Polly and Digory went home that later that day, and were always friends.
Polly lived a full and happy life. She never married, but stayed in touch with Digory. In 1949, she got the Seven Friends of Narnia together to talk about Narnia. A week later, she died in a British Railway Accident at the age of 60. Polly was then able to enter Aslan’s County forever, where she witnessed the End of Narnia, and was reunited with her Narnian friends.