Mrs. Hawkins runs the Admiral Benbow Inn where Captain Billy Bones comes to stay, hiding from a “seafarin’ man with one leg.” The townspeople flock to hear his stories, though Dr. Livesey, the town doctor and magistrate, threatens to throw him out of town if he causes any trouble.

Black Dog the pirate finds Billy at the Inn and attacks him and runs, leaving him for dead. Mrs. Hawkins and Jim rummage through Billy’s treasure looking for money to cover the debts that he owed to her. They barely escape before pirates enter, but they do find a treasure map to the infamous pirate Captain Flint’s treasure. The pirates ransack the Inn trying to find Billy’s map, with no success.

Jim and the constable visit the wealthy Squire Trelawny and show him the map. In his excitement to find the treasure himself, he puts up money for a ship and crew to set sail immediately.

Their adventure starts off smooth enough—until Jim overhears the ship’s cook, Long John Silver, and other sailors discussing a planned mutiny after they find and load Captain Flint’s treasure. It turns out that Silver and most of the sailors were actually Flint’s pirate crew and they have no intention of letting the honest men onboard return alive with the treasure. Jim tells Squire, Livesey, and the ship’s captain, Captain Smollett, of the treacherous plan; and they decide they must create their own counterattack.

The ship reaches the island where the treasure is supposed to be hidden, and a group of pirates go ashore. Jim sneaks to shore, as well, and discovers a man named Ben Gunn who had been living there for the last three years, because he was marooned by his crewmates when they were searching for Flint’s treasure. He agrees to help Jim and his friends escape safely.

The honest men, led by Captain Smollett, decide there is more safety in abandoning ship and going ashore to seek shelter in an old shed depicted on the treasure map. They manage to get away from the pirates on board, find the shed, and hold their position against an attack by the pirates who came ashore. Jim manages to slip away from the group and returns to the ship. Through a series of fortunate events, he regains control of the ship from the pirates.

With people spread all over the island, adventure builds to a crescendo with a volley of skirmishes, desertions, truces, deceptions, bargains, and a fight for the hidden treasure! But only one side can win and find the hidden treasure. Which will it be?