As in the earlier The Muppet Christmas Carol, the key roles were played by human guest stars - in this case, Tim Curry as Long John Silver and Kevin Bishop as the putative protagonist Jim Hawkins - while the Muppets filled in supporting roles, including Kermit the Frog as Captain Smollett Trelwaney, Fozzie Bear as Squire Trelwaney, and Miss Piggy as Benjamina Trelwaney. Following their success as the narrators of The Muppet Christmas Carol, The Great Gonzo and Rizzo appear in specially-created roles as Jim Hawkins, and steal the show.
The film featured a non-specific reference to the "Big Blue Wet Thing," though Silver (using the stars) determines they are heading southwest. The only ocean they could be in is the Pacific Ocean if they set off from England. While featuring the Muppets' usual good-natured slapstick humor, several musical numbers, and the occasional twist, the film stays fairly true to the familiar Stevenson storyline.
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the entire movie.
Jim and his friends travel to Bristol to obtain a ship to find the treasure and meet with Squire Trelawney (Fozzie Bear), who agrees to finance the voyage (he is clearly eccentric and believes a character called 'Mr. Bimbo' lives in his finger). On the ship Hispaniola, Jim and the others meet the crew for the voyage, including uptight First Mate Samuel Arrow (Sam the Eagle) and ship's cook Long John Silver (Tim Curry). Gonzo is suspicious of one-legged Silver, as Billy Bones frequently warned of a 'one-legged man', but Jim doesn't agree. The voyage begins after no-nonsense Captain Abraham Smollett (Kermit the Frog) arrives and they set sail in high spirit ("Sailing for Adventure").
It becomes evident though during the roll call, that the crew all seem to be scoundrels. Trelawney admits that 'Mr. Bimbo' has recruited them, as it was on the advice from Silver. Captain Smollett's doubts about them are given credence when Polly (Silver's pet lobster), Clueless Morgan and Mad Monty kidnap and torture Gonzo and Rizzo to learn about the location of the rumored treasure map. They are caught in the act by Mr. Arrow who then locks them up in the brig on Smollett's orders. Following this incident, Smollett has Mr. Arrow lock the map in his cabin. While discussing this with his new friend Silver, Jim accidentally mentions that there is a map and its location. Playing on Mr. Arrow's doubts about the safety of the ship, Silver tricks him into rowing away from the Hispaniola to test a lifeboat. Mr. Arrow falls for it and leaves Silver with his keys, having reasoned that it would be disastrous if the keys were to fall overboard. Silver and the crew convince everyone else that Mr. Arrow drowned. During their voyage, the wind dies and they are left at a standstill in the ocean, causing them to temporarily become insane with cabin fever ("Cabin Fever").
While snacking on some apples in a barrel, Jim, Gonzo and Rizzo overhear Silver warning the escaped Polly, Clueless Morgan, and Monty to not mutiny until he says so and reveals his involvement in Mr. Arrow's disappearance. Jim finally realizes that Silver is a villain. Captain Smollett, alerted to Silver's treachery by Jim, convinces Silver to take the crew ashore as they approach Treasure Island planning to abandon them there. However, Silver is wise to the captain's plan and kidnaps Jim. Silver tries to convince Jim that he should join the pirates ("A Professional Pirate") as Captain Smollett, Gonzo and Rizzo row ashore to attempt a rescue. Unfortunately, this leaves the ship open to take over by a few pirates who stayed behind and easily overpower the Squire, Dr Livesey (Bunsen Honeydew) and Beaker. Jim is forced to help the pirates find the treasure using his father's compass, but there is no treasure and the pirates turn against Silver for having them turn to mutiny against the captain for nothing. Silver holds the pirates off after forcing Jim to escape, stating that liking Jim as a friend is the one thing Silver didn't lie about.
Meanwhile, Captain Smollett, Gonzo and Rizzo are captured by the wild boar tribe native to the island and brought before their queen ("Boom Shakalaka"), who turns out to be Benjamina Gunn (Miss Piggy), a former fiancée of the captain. While she berates Smollett for having jilted her years ago, Jim rescues Gonzo and Rizzo. They return to the ship with the aid of Mr. Arrow, who suddenly turns up in his lifeboat alive, and scare the pirates away by having Mr. Arrow pose as his own ghost. The other pirates decide to kill Silver and give him the Black Spot (that Monty drew on a page torn from a Bible), but Silver plays on their fears and superstitions and tricks them into reinstating him as their leader. Meeting up with the captain and Benjamina (who, it turns out, also had a fling with Silver and also Captain Flint who marooned her), Silver threatens to drop Smollett off a cliff unless Benjamina tells him where she hid the treasure (which she took for herself). Once she tells him though, the pirates leave them both facing a plunging doom. Smollett assures Mina that at least they are together again ("Love Led Us Here").
Captain Smollett and Mina are rescued by Jim and the others aboard the Hispaniola and they battle the pirates, ultimately winning the help of the local tribes and Sweetums (who was actually on Smollett's side). They load up the treasure and prepare to return to England with the pirates in the brig, but Silver escapes (since he still had Mr. Arrow's keys with him) and flees in a lifeboat with some of the treasure. Jim catches him escaping and Silver attempts to shoot Jim, but ultimately decides he can't kill the boy. Touched by this, Jim advises Silver to just leave and he does. Smollett, having witnessed this, assures Jim that he did the right thing, and that his father would be proud. However, Mr. Arrow reveals to Jim and the captain that the lifeboat Silver took has a leak. The boat sinks and Silver is left marooned on the treasure island as Jim and the others—joined by Mina's tribe—set sail again, this time to "wherever the wind may take us". The crew of the Hispaniola sail off into the sunset while some scuba-diving rats recovers the treasure.
During the credits, an Island Head tells a marooned Long John Silver a joke that goes "Why does the ocean roar? Give up? You would too if you had crabs on your bottom and oysters in your bed."
- Muppet Performers
- Dave Goelz - Gonzo, Zoot, Rizzo the Rat (puppeteer), Undertaker (puppeteer)
- Steve Whitmire - Kermit the Frog, Rizzo the Rat, Walleye Pike, Inkspot, Gonzo (puppeteer)
- Jerry Nelson - Floyd Pepper, Statler, Mad Monty, Inkspot, Blind Pew, Old Tom
- Kevin Clash - Polly Lobster, Spa'am, Black Dog, Real Old Tom; puppeteer for Miss Piggy, Fozzie Bear, Sam the Eagle (some scenes), Mr. Bimbo
- Bill Barretta - Clueless Morgan, Flaubert, Angel Marie, Mudwell the Mudbunny, Mr. Bitte, Pigs; hands for Blind Pew
- John Henson - Sweetums, Island Head
- Frank Oz - Miss Piggy, Fozzie Bear, Animal, Sam Eagle
- Louise Gold - Rat, Laundress (puppeteer), Begoony (puppeteer), Dr. Bunsen Honeydew (puppeteer), Beggar (puppeteer), Beaker (puppeteer), Sweetums, Clueless Morgan (right hand), Jacques Roach (puppeteer)
- Nigel Plaskitt - Skull
- John Eccleston - The Dodo
- Simon Buckley
- Katherine Smee - Inkspot, Chicken, Dr. Bunsen Honeydew (right hand), Beaker (right hand), Sam the Eagle (right hand), Mad Monty (right hand)
- Andrew Spooner - Pig, Inkspot, Cow, Beaker (puppeteer), Black Dog (right hand), Begoony (puppeteer), Dr. Bunsen Honeydew (puppeteer), Rizzo the Rat (puppeteer), Old Tom (puppeteer)
- Robbie Barnett - Angel Marie (puppeteer)
- James Barton
- Michael Bayliss
- Charles Broughton
- David Bulbeck
- Dave Chapman - Old Joe (puppeteer), Dr. Bunsen Honeydew (puppeteer), Winny (puppeteer), Sam the Eagle (right hand)
- Marcus Clarke -
- Sue Dacre -
- Taylor David -
- Geoff Felix -
- Mike Gallant -
- Pat Garrett -
- Barnaby Harrison -
- Mark Jefferis
- William Todd Jones
- Robin Kingsland
- Steve Kynman
- Christopher Leith
- Anthony Lymboura
- Mark Mansfield
- Joan Morris
- Rebecca Nagan
- Margaret O'Flaherty
- Angie Passmore
- Peter Passmore
- Marie Phillips
- Colin Purves
- Mike Quinn
- Axel Rathgeber, Peter Robbins, Gillie Robic, Helena Smee, John Thirtle, Ian Thom, Heather Tobias, Jurgen Tombers, Ian Tregonning, Rob Tygner, James Vaughan, John Wheatley, Victoria Willing, Phil Woodfine, Sarah Wright, Paul Zerdin, and Karen Prell (uncredited)
- Background Muppets (non-speaking)
- Floyd Pepper, Zoot, Animal, Janice, Dr. Teeth, the Swedish Chef, George the Janitor, Rowlf, Robin the Frog, Bean Bunny, Inkspots, Link Hogthrob, Crocodile, Monkey, Snakes, Skulls, Sprocket the Dog, Flaubert, J.P. Grosse, Pops, Mr. Plagueman, Winny, Eugene, Droop, Koozebanian Phoob, Laundress, Whatnots, Rats, Island Heads, Raccoons, Aretha, Pigs, Chickens, Dogs, Wolfhound, Cow,Goat, Moose Head, Bananas, Cactus, Green Frackle