Magical Suitcases and Trunks

• Type: Magical Device, Storage
• Owners: Alastor Moody, Hermione Granger, Newt Scamander (film)
• Maker: Unknown

Magical suitcases and trunks are containers, often ordinary in external appearance, that have been enchanted to possess properties far beyond their mundane counterparts. The most common enchantment is the Undetectable Extension Charm, which vastly increases the internal dimensions without altering the external size or weight.

• Alastor Moody's Trunk: A large, heavily battered magical trunk secured by seven different locks on its lid. Each lock corresponds to a separate, magically distinct compartment within. The trunk is old and covered in labels from its travels around the world.
• Hermione Granger's Beaded Handbag: A small, purple, beaded handbag that, to a casual observer, appears to be an ordinary accessory. Despite its diminutive size, it is enchanted to hold a vast quantity of items.
• Newt Scamander's Suitcase: A well-worn, brown leather suitcase of standard size. It features a special dial that can engage a “Muggle-Worthy” setting, which displays a mundane interior to non-magical observers. (film)

The primary function of these items is to carry significantly more than their physical size would allow, making them invaluable for travel or concealment.

• Undetectable Extension Charm: This is the core enchantment used on items like Hermione's handbag. It makes the internal space of the container magically larger. Hermione Granger used her bag to carry a large tent, numerous books from Albus Dumbledore's office, changes of clothes for herself, Harry Potter, and Ron Weasley, a full stock of potions and ingredients like Essence of Dittany, the Sword of Gryffindor, and various other necessities for their year-long hunt for Horcruxes.
• Multi-Compartment System: Alastor Moody's trunk was a far more complex magical object. Each of its seven locks opened a unique compartment. While the contents of all compartments are not detailed, they were used for different purposes. The seventh and final compartment was a magically created chamber, described as a ten-foot-deep pit, where Barty Crouch Jr. imprisoned the real Alastor Moody for nearly a full school year. This compartment was furnished and sustained Moody, allowing Crouch to keep him alive for information and for hair to use in Polyjuice Potion.
• Weight Concealment: It is implied that these containers are also enchanted to be lighter than the sum of their contents, as Hermione could carry her heavily-laden bag with ease.
• Habitat Creation: Some magical suitcases can contain entire magical environments. Newt Scamander's suitcase housed a vast menagerie of magical creatures in self-contained, magically-replicated habitats. (film)

The use of magically expanded containers is a known practice in the wizarding world, though their creation is regulated by the Ministry of Magic. Barty Crouch Jr., disguised as Alastor Moody, brought the seven-locked trunk to Hogwarts in 1994. He used it as the cornerstone of his plot to circumvent the security of the Triwizard Tournament and deliver Harry Potter to Lord Voldemort. The trunk's existence and purpose were only discovered after Harry returned from the Little Hangleton graveyard, when Albus Dumbledore grew suspicious and forced it open, revealing the captive Moody. Hermione Granger prepared her enchanted beaded handbag prior to Bill Weasley and Fleur Delacour's wedding in the summer of 1997. She packed it in anticipation of having to make a sudden escape, a foresight that proved crucial when Death Eaters attacked the wedding reception. The bag became an indispensable tool for the trio's survival and mission throughout Harry Potter and the Deathly Hallows.

Magical trunks and bags serve as critical plot devices. Moody's trunk was the mechanism of the central deception in Harry Potter and the Goblet of Fire, enabling Barty Crouch Jr.'s infiltration of Hogwarts and manipulation of events. Its discovery was the key to unraveling the conspiracy behind Voldemort's return. Hermione's handbag symbolizes her preparedness, intelligence, and practicality. It was a literal lifesaver for the trio during their hunt for Horcruxes, providing them with shelter, supplies, and crucial magical items when they were isolated and on the run. The bag represents a portable safe haven and a library of resources in a time of great uncertainty.

• The most famous example of a magical suitcase in the wider wizarding world is the one belonging to Newt Scamander, the protagonist of the Fantastic Beasts and Where to Find Them film series. His suitcase, which contains dozens of magical creatures, is central to the plot of the first film. (film)
• The concept of a magically-expanded container is a common trope in fantasy literature, often referred to as a “bag of holding.”
• The Undetectable Extension Charm is noted to be a difficult piece of magic. Its misuse is governed by the Ministry of Magic, as Arthur Weasley was fined for enchanting his Ford Anglia with a similar charm.