Two-Way Mirrors

• Type: Magical Device, Communication
• Owners: James Potter and Sirius Black (original pair); later Harry Potter and Aberforth Dumbledore
• Maker: Unknown

A Two-Way Mirror is a small, portable mirror used for communication. The one given to Harry Potter by Sirius Black was described as a square mirror, small enough to fit in a pocket. When inactive, it appeared somewhat grubby and unremarkable. When Harry Potter later smashed his mirror in a fit of grief, he kept a single sharp-edged shard. This shard, despite being a fragment, retained its magical connection to its counterpart.

The primary function of a Two-Way Mirror is to provide instantaneous, two-way visual and auditory communication between the holders of a matched pair. To activate it, the user holds their mirror and clearly states the name of the person holding the other. The recipient's face will then appear in the mirror, and a conversation can be held, regardless of the distance between the two users. The magic persists even if one of the mirrors is broken. A shard of a mirror is still connected to its intact counterpart. While a full conversation is not possible through a shard, the holder of the whole mirror can see the surroundings of the person carrying the shard. The person with the shard can also see glimpses of the other user, such as an eye looking back, and can use it to make a general plea for help that will be understood by the person on the other end.

A pair of Two-Way Mirrors was owned by best friends James Potter and Sirius Black during their time at Hogwarts School of Witchcraft and Wizardry. They used the mirrors to communicate with each other while serving separate detentions. After James's death, Sirius kept both mirrors. In 1995, Sirius gave James's old mirror to his godson, Harry Potter, just before Harry returned to Hogwarts for his fifth year. He presented it as a way for Harry to contact him if Severus Snape was giving him a hard time. However, Harry, determined not to lure Sirius from the safety of Number Twelve, Grimmauld Place, never unwrapped the package and forgot about it. He only rediscovered it after Sirius's death, and in his grief and regret, he smashed it on the floor of his trunk. Following Sirius's death, his mirror was stolen from Grimmauld Place by Mundungus Fletcher, along with other Black family heirlooms. Mundungus later sold the mirror to Aberforth Dumbledore, the bartender at the Hog's Head Inn. Unbeknownst to Harry, Aberforth was able to use his mirror to keep an eye on Harry, who had decided to keep a shard of his own broken mirror with him.

In Harry Potter and the Order of the Phoenix, the mirror represents a missed opportunity and becomes a source of profound regret for Harry. His refusal to use it to contact Sirius before rushing to the Department of Mysteries is a key element of the book's tragic climax. Its discovery and subsequent destruction by Harry is a powerful symbol of his grief. In Harry Potter and the Deathly Hallows, the shard of the mirror becomes a vital plot device and a symbol of hope. Harry frequently sees a flash of a bright blue eye, which he mistakes for that of Albus Dumbledore, watching him through the fragment. This gives him a feeling of being protected. The shard's most critical role occurs when Harry, Ron Weasley, and Hermione Granger are imprisoned in the cellar of Malfoy Manor. In desperation, Harry pleads for help into the shard, and his call is answered by Aberforth Dumbledore, who sends Dobby the house-elf to rescue them. This act directly saves the lives of the trio and their fellow prisoners, allowing them to continue their quest to destroy Voldemort's Horcruxes.

• In the film adaptation of Harry Potter and the Order of the Phoenix, the Two-Way Mirrors are completely omitted. This created a potential plot hole for the Deathly Hallows films. To resolve this, the Harry Potter and the Deathly Hallows – Part 1 film re-introduces the mirror shard, which Harry finds in his trunk, but does not explain its origin from Sirius. (film)