Fantastic Beasts Film Will Finally Explain What Happened To Dumbledore's Sister

Harry Potter fans are finally going to get to the bottom of what happened to Dumbledore's mysterious sister in the new Fantastic Beasts film.

In Fantastic Beasts: The Secrets Of Dumbledore, the powerful wizard (played by Jude Law) will gather everyone he can to join him in the war against Gellert Grindelwald (Mads Mikkelsen) - including his estranged brother Aberforth (Richard Coyle).

Reuniting for the first time in decades, Albus and Aberforth will finally face the tragic story of their sister Ariana.

Some hardcore Potterheads may remember the story of Ariana Dumbledore as told in Harry Potter and the Deathly Hallows, when Harry, Ron, and Hermione meet Aberforth at the Hog's Head Inn.

But it looks like The Secrets Of Dumbledore is set to give fans a clear visual on what went down between the Dumbledore siblings - and how Grindelwald was involved.

So, for those who can't quite remember how the drama unfolded, here's what we know from Aberforth's brief explanation in The Deathly Hallows:

When Ariana was just six years old, she was brutally attacked by a group of Muggle boys. Seeking revenge, her father Percival attacked the Muggles, for which he was sent to Azkaban.

Warner Bros.)

The Dumbledore family moved to Godric's Hollow, keeping Ariana hidden while Albus and Aberforth attended Hogwarts.

When their mother died, Albus returned home to Godric's Hollow take care of Ariana while Aberforth continued his studies.

At the same time, expelled student Gellert Grindelwald travels to Godric's Hollow to research the Deathly Hallows, where he meets Albus. The two become incredibly close.

Eventually, Aberforth expresses his concern over his brother's connection to Grindelwald, as well as Ariana's wellbeing. He confronts Albus and Grindelwald when their plans get out of hand, and the three wizards end up in a duel.

Warner Bros.)

At some point during the battle, a stray curse struck and killed Ariana.

The Dumbledore brothers saw each other one last time at Ariana's funeral where they got into a physical fight that left Albus with a broken nose.

In the latest instalment of the Fantastic Beasts series, fans will learn even more about the Dumbledore siblings, as well as the nature of Albus' relationship with Grindelwald.

Fantastic Beasts: The Secrets of Dumbledore is now screening in theatres across the UK.