Film buffs love to think that they know every detail of their favourite flicks, but there are always secrets lurking in their cinematic depths.
Take the Harry Potter universe for example.
With eight films and one spin-off out so far there are bound to be a few things that even the most observant of fans have missed.
Not so long ago, people learned that there was a reference to the hero of Fantastic Beasts and Where To Find Them in The Prisoner of Azkaban.
That movie (which is easily the best Harry Potter film) has come up trumps again with a newly unearthed gem, which is actually amazing.
Around 25 minutes into the movie, just as the students are reacquainting themselves with Hogwarts, there is a scene where Harry and his mates are trying to gain access to the Gryffindor common room.
To do this they have to give the password "Fortuna Major" to the painting of The Fat Lady, played by Dawn French.
Now, The Fat Lady is awful at singing, much to the dismay of the other paintings around her. Except one.
Positioned just below her is a portrait of "He Who Must Not Be Named" aka Lord Voldemort, who is blissfully dancing away to the Fat Lady's dulcet tones.
Here's a photograph for proof.
OK, you'll probably want a bit more evidence than that.
Here's a video. Be sure to look to the right of the staircase at the 1:17 mark to see the Dark Lord doing his thing.
We're not sure who we should thank for this incredible moment in cinema history, but we're really happy that it exists.
HT Lad Bible