Preface: I have no clue what actually happens in The Lord of the Rings. Here's what I know with some embellishments.
Book 1: The Fellowship of the Rings
Sam Baggins and Bodo Baggins are the main characters. They are brothers that live in Middle Earth. It's really mossy. However, poor Bodo is allergic to the moss, and plot twist, his allergic reaction makes him really fluffy and Sam decides to hide him because he was made fun of in the village. Sam decides to call him Frodo and no one knows Frodo is related to Sam.
Soon enough Sam and Frodo become estranged because Sam has his own friends and Frodo became friends with the other outcasts. In Middle Earth friend circles are called rings (this will be important later). Sam and Frodo are living their lives happy, but they miss each other. However, years later, havoc is coming to Middle Earth and Gandalf the Grey is torturing dragons. Oh no! Dragons are a common transportation in Middle Earth, and now that they are being tortured Middle Earthians are being forced to walk everywhere. And Middle Earthians walk a lot. They walk for most of the book/movie, trying to gather people to help fight against Gandalf the Grey.
One day Sam Baggins, with his silky golden hair, gets a knock on his door. He opens it to find his brother Bodo... excuse me, Frodo, is standing there fluffy as ever. Frodo sees Sam and remembers him. They talk about Gandalf the Grey and decide to get rings together to fight against him. They created a fellowship of their rings! Huzzah!
Book 2: The Two Towers
Gandalf the Grey continues terrorizing Middle Earth one dragon at a time. Sam and Frodo and their rings get together in a mossy alcove to think of plans to take down Gandalf. One day they hear a knock at the door. Frodo goes to the door and opens it to find a dark-haired, legless man sitting at the door. The legless man, named Legoless, arrests Frodo for conspiring against Gandalf the Grey. Legoless also wants to arrest the other people of the ring, but can't because they run away.
Now the anti-Gandalf coalition, who call themselves the Hobbits, need somewhere to meet. By now they have over 50 people in the group... which makes it hard to find one spot to fit all of them. Plus, Frodo is gone and they have to figure out how to find him and release him.
Sam and the ring find a little alcove to devise a plan to find Gandalf. They must walk to the outskirts of Middle Earth and find Galdolf's headquarters. After months of planning, they walk and walk and walk and eventually they reach the horizon, where they see two towers looming above the land. The groups decide to split up to search the two towers. Chaos ensues.
Sam finds Legoless in the left tower. Sam and Legoless fight until finally, Sam overtakes Legoless and demands that he tell him where Gandalf is. Legoless admits that Gandalf is upstairs in his office. Sam reaches the top of the tower and finds Gandalf. Gandalf is sitting in his desk chair looking out over the field where they torture the dragons, smiling eerily.
Sam is ready to kill ratty old Gandalf... it's not like he's that far from death anyway. Instead of fighting back, Gandalf tells Sam that he knows all about Bodo Baggins, his real brother, and he thinks he has a cure for Bodo's moss allergy. Sam is intrigued. That's the last thing he thought Gandalf the Grey would say. But Sam believes him, if only because he hopes that the old geezer is telling the truth. (such a cliffhanger)
Book 3: The Last Jedi (I literally have no clue what its actual title is)
Sam and Gandalf are alone in the left tower. Frodo is absent. Sam is contemplating the new information. Sam remembers why he originally broke into the tower. He asks Gandalf why he is torturing dragons. Gandalf tells Sam about how a rogue dragon threw off his son, Legoless, when he was young, causing the boy to lose both of his legs and be an outcast from society. Sam argues that you can let one bad seed determine one's opinion about the whole breed.
Gandalf laughs at young Sam. He asks Sam to take a walk with him. They walk (a lot) and talk. Gandalf tells Sam about how the dragons he stole and tortured are owned by the people that made fun of Legoless. At first, he wanted to get back at the people, not the dragons. As time went on, Gandalf began to see his errors but didn't want to quit altogether for fear of people not thinking he was powerful.
Then, when Legoless brought Frodo to the right tower to be imprisoned, Gandalf was very intrigued about the furriness of Frodo because he had never seen someone like him. He talked to Frodo and Frodo explained how he was allergic to moss, causing him to grow fluffy white hair everywhere. Gandalf had a soft heart for outcasts like Frodo and Legoless and it was then that Gandalf realized that if he found a cure for the moss allergy, then he would be well known in Middle Earth and beyond. He could stop torturing dragons and start helping people.
After they had been walking for hours, Sam asks Gandalf what the cure is. Gandalf explains that an injection of dragon tears will alleviate the furriness for a month... they tested it on Frodo. Sam asks how Frodo is. Gandalf explains that the tests went wrong a lot, but Frodo should live. Sam is horrified but then asks how to get dragon tears without hurting the dragons. Gandalf chuckles and tells Sam that the dragons love being tickled so much they laugh until they cry. Certified dragon trainers then capture the tears and use them in the medicine.
Concluding the walk, Gandalf takes Sam to see Frodo. When Sam sees his hairless brother, he thinks back to their childhood and hugs his brother. "It's good to see you Bodo."
The end.