Even before Disney bought the rights to them, one key factor that makes the Muppets movies so popular is the songs. Ranging from upbeat Broadway-style numbers to gentle songs from the heart, the Muppets' musical abilities have shown no limits and nothing will stop them from singing a little song, even being frozen to a gulag wall.

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Throughout the years, the songs have become iconic for many Muppet fans, particularly for certain generations. And due to being quite a few across at least eight movies, some songs have stood out more than others, and can happily be stuck inside a Muppet fan's head for a long time.

"Shiver My Timbers" (Muppet Treasure Island)

Pirates and tropical creatures sing to set the tone in Muppet Treasure Island

Many people who grew up in the 1990s can agree that most of the songs in Muppet Treasure Island are fantastic, and the first song "Shiver My Timbers" is one of the best of the best.

"Shiver My Timbers" perfectly sets the mood for the swashbuckling adventure that lies ahead. Although no main Muppets sing in it, assorted puppets including various creatures, skulls, and pig statues welcome the audience along with the chanting pirates carrying Captain Flint's treasure to its hideout. With the song ending on "dead men tell no tales" and a gunshot, it's more worthy of any Pirates of the Caribbean movie.

"We're Doing A Sequel" (Muppets Most Wanted)

The Muppet cast sing We're Doing A Sequel from Muppets Most Wanted

Although the movie works very well as a standalone, Muppets Most Wanted is the sequel to The Muppets that was released in 2011. The first scene picks up right at the end of the 2011 Muppets movie, and initially unsure what to do, the Muppets (with the help of Ricky Gervais) decide that they're "doing a sequel."

A combination of classic Hollywood movie sets and Muppet quirks, "We're Doing A Sequel" is an excellent start to the movie. It's a toe-tapping earworm that's easy to hum along to even if it's the first viewing. It even takes a hilarious dig at The Godfather Part III and somewhat prophesized Toy Story 4. And let's not forget a very brief cameo from Tony Bennet and Lady Gaga singing about "Hollywood stars and one-liner cameos."

"Scrooge" (The Muppet Christmas Carol)

Michael Caine Scowling as Scrooge in the Muppet Christmas Carol

The Muppet Christmas Carol is a holiday classic for many and is considered both one of the best Muppet movies and one of the best movie versions of A Christmas Carol ever. And although the character of Ebenezer Scrooge really needs no introduction, the Muppets do so anyway. And what better Muppet introduction than a song?

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As Michael Caine's Scrooge strolls through the snowy streets, surrounding Muppets (including Muppet vegetables) sing of how heartless and ruthless he is. Even non-Muppet fans find themselves singing the lines "There goes Mr. Humbug, there goes Mr. Grim." after hearing the song just once.

"Can You Picture That?" (The Muppet Movie)

The Electric Mayhem sing Can You Picture That from The Muppet Movie

The Muppet Movie tells the story of how Kermit met the Muppets whilst simultaneously journeying to Hollywood and running away from an evil spokesperson called Doc Hopper. Early in his trip, Kermit and Fozzie meet the Electric Mayhem, who disguise Fozzie's car to help them escape Hopper.

Whilst they do this, they sing "Can You Picture That?", a groovy rock number that is a firm favorite among Muppet fans. The Electric Mayhem is among Jim Henson's iconic creations, and this song is understandably considered one of their best. Although the lyrics are completely out there, it's hard not to headbang and sing along with the beloved Muppet rock band.

"A Professional Pirate" (Muppet Treasure Island)

Long John Silver with Sweetums and another pirate in Muppet Treasure Island

One of the many great things about Muppet Treasure Island is casting the legendary Tim Curry as Long John Silver. Curry is extremely charming and lovable as the peg-legged villain, and thankfully for fans, Curry treated viewers to another villainous song to add to his repertoire.

Sung at night around a blazing campfire, and with the pirate crew as backup singers, "A Professional Pirate" is a belter of a tune and the ultimate villainous pirate track. Yet surprisingly, despite his musical talents, he only has one solo song, something that Silver is very keen to point out mid-song.

"Life's A Happy Song" (The Muppets)

Promotional Poster for The Muppets (2011) featuring the cast of characters

After about twelve years, the Muppets made their cinematic comeback in the form of The Muppets. However, they interestingly don't appear in the movie until about a quarter of the way in.

Instead, the movie introduces the new Muppet Walter, his human brother Gary (Jason Segel), and the latter's girlfriend Mary (Amy Adams in her most family-friendly role), through the musical number "Life's A Happy Song." Whilst sang by predominantly humans in the style of a Broadway musical, the song lives up to its title and is a joyful tune to listen to. There's also a brief appearance of the late and great Mickey Rooney.

"Happiness Hotel" (The Great Muppet Caper)

The Muppet cast sing Happiness Hotel from The Great Muppet Caper

The Great Muppet Caper saw reporters Kermit, Fozzie and Gonzo travel to London in order to investigate a high-profile robbery. With no money in their pockets, the trio looks for a place to stay for free, and at the recommendation of an English gentleman, they find the Happiness Hotel.

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The hotel itself may be a health inspector's worst nightmare but the place is immediately warmed up by the weirdly welcoming song performed by the Muppet cast. Most people would run for it if they heard a hotel treat pests like guests but with the upbeat lyrics and Muppet zaniness, it proves to be as infectious as whatever's lurking in the hotel.

"Sailing For Adventure" (Muppet Treasure Island)

Sam the Eagle and Fozzie Bear in Muppet Treasure Island

Another particularly great song from Muppet Treasure Island is "Sailing for Adventure." This is where the ship sets sail for Treasure Island, and the entire crew breaks into song to celebrate.

The song is already perfectly set for any pirate adventure, and because of some of the wacky lyrics sprinkled in, it's even better suited for a Muppet pirate adventure. Particular highlights include "margaritas at the midnight buffet!" and "sailing for adventure on the big blue wet thing...", the latter causing an already bemused Sam the Eagle to briefly break the fourth wall with an exasperated stare.

"Rainbow Connection" (The Muppet Movie)

Kermit sings Rainbow Connection in The Muppet Movie

Arguably the most iconic song from the Muppets as a franchise is "Rainbow Connection." The song features at the start of The Muppet Movie, in which Kermit sat on top of a log in his swamp, banjo in hand as he sings the beloved melody.

"Rainbow Connection" is a beautiful and gentle song, showing not only that the Muppets have heart as well as humor but it has become somewhat spiritually representative of Jim Henson himself. The memorable chorus is among some of the best quotes from the Muppet movies.

"It Feels Like Christmas" (The Muppet Christmas Carol)

Ghost of Christmas Present and Scrooge (Michael Caine) in The Muppet Christmas Carol

It is fair to say that all of the songs from The Muppet Christmas Carol are fantastic, heartwarming, and unforgettable. And perhaps the best of the songs, and perhaps the best Muppet movie song overall, is "It Feels Like Christmas."

Sung by the jovial Ghost of Christmas Present, "It Feels Like Christmas" is a true Christmas classic. It's joyful, festive, and full of heart, with a dash of Muppet humor for good measure. It's so much so that even Scrooge is smiling and dancing along. It is perhaps during this song that Scrooge starts to become a kinder and warmer person.

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