20 details you probably missed in 'The Nightmare Before Christmas'

The movie's introduction, set to the song "This Is Halloween," traverses through a graveyard with ghostly shadows reflected on the tombstones.

The first ghost appears to be pretty classically shaped, and the second looks like a dog or werewolf. But the third ghost, which is the eeriest of the three, seems to be a two-headed woman, or maybe a set of conjoined twins.

The Mayor of Halloween Town has an unusual appearance.

Although most viewers probably picked up on his character's head-swiveling design being a play on the phrase "two-faced politicians," some may have missed that his tie is a spider.

Similarly, Jack's tie is shaped like a bat.

The Mayor gives out prizes after the successful Halloween night, and the vampires win the gruesome award for "most blood drained in a single evening."

The Dark Lagoon leeches also receive an honorable mention for the same award.

While singing "Jack's Lament," Jack removes his head and holds it in his hand, singing "And since I am dead, I can take off my head to recite Shakespearean quotations."

This seems to be a not-so-subtle reference to the well-known scene in Shakespeare's "Hamlet" where the titular prince holds a skull while reciting his "To be, or not to be" soliloquy.

Halloween Town is full of unique and spooky decor, and Jack's house is no exception.

When the Mayor visits Jack, he rings the doorbell by pulling on a dead spider attached to a pulley. The doorbell sounds like a woman's scream, and the knob is an eyeball.

When the Mayor goes to Jack's house to discuss plans for next Halloween, he becomes increasingly agitated when Jack doesn't answer the door. At one point, he exclaims, "I'm only an elected official here. I can't make decisions by myself."

This, combined with the Mayor literally being "two-faced," adds to the satirical nature of the character.

Though Jack ends up going into the Christmas Town portal, there are six other doors visible in the clearing, including one for Independence Day, Valentine's Day, St. Patrick's Day, Easter, and Thanksgiving.

When Jack returns from Christmas Town, he asks the Mayor to call a town meeting so he can tell everyone what he's discovered.

During the meeting, Jack speaks at a podium in the shape of a coffin. The curtain hanging behind him seems to be decorated with broken hearts that have been stitched back together.

When Jack reads a large stack of books about Christmas, most of the titles are just generic phrases connected to the holiday, such as "Santa," "Noel," and "Xmas."

However, Jack also reads some recognizable stories from the real world, including "A Christmas Carol" and "Rudolph."

As Jack attempts to figure out what Christmas is all about, he writes out a "formula" that's full of typical holiday traditions.

Viewers can clearly see the phrases "sugar plum visions" and "egg nog" at the top of the board, and underneath, he divides "chestnuts" over "open fire."

The date "12.25.93" is also a reference to the year the movie came out.

Jack has metal frames on his windows that are shaped like bats and jack-o'-lanterns.

This matches his gate, which has a jack-o'-lantern design on the top of it — all appropriately spooky features for the Pumpkin King's house.

Oogie Boogie's henchmen, also known as Boogie's Boys, are named Lock, Shock, and Barrel.

This is likely a pun on the phrase "lock, stock, and barrel," which informally refers to a complete set of something, but the phrase itself is also a reference to various parts of a gun.

As the three characters are never seen without each other, and work together to cause chaos, their names suit them well.

The Boogeyman's lair is full of spooky casino decorations.

The floor itself looks like a roulette wheel, with unlucky symbols on the slotted spaces such as a black cat and the number 13. There are also skeleton dice with skulls on them, and the middle of the roulette wheel features an oversized eight ball as well.

When Oogie Boogie rolls a pair of "ones," snakes come out of the holes — a clever visual representation of the common phrase "snake eyes."

During Jack's presentation about Christmas, one of the audience members who asks a question is a witch. She pulls up her hat to reveal another witch who pulls off her hat to reveal yet another witch, and so on.

Later, when the town members are shown making toys for Christmas, the same witch is making a set of nesting dolls, which is pretty fitting given her situation.

When Lock, Shock, and Barrel attempt to shove Santa down the tube that leads to Boogie's lair, viewers can see that he's is wearing underpants with a mistletoe pattern — a fitting clothing choice for the leader of Christmas Town.

When the Mayor gives a speech before Jack flies off to Christmas Town, he's holding a piece of parchment paper in his hands.

If viewers look closely, they can see that the speech is actually written out, word for word, on the paper.

When he first appears, Jack's dog, Zero, has a glowing orange nose. At the beginning of the movie, this appears to just be a part of his appearance. However, when fog makes it impossible for Jack to take off on his sleigh on Christmas Eve, Zero guides it like Rudolph the Red-Nosed Reindeer.

This was actually foreshadowed earlier in the movie when Jack was reading the "Rudolph" book.

Jack's sleigh, like the podium seen earlier at the town meeting, is shaped like a coffin.

The top has an opening, and viewers can even see that satin-looking fabric inside resembles that of most real coffins. The front of the sleigh also features metal teeth, and it's being pulled by reindeer skeletons.

When Jack delivers presents in Christmas Town, some adults' faces are blocked in creative ways. For example, one mother's head is cut off by window shades, and a radio announcer's face is completely out of frame.

However, when Jack first arrives, a grandmother can be seen reading to children in front of a fire, so there appears to only be a certain generation of adults who get blocked.

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