There's actually several end credit scenes in Ghostbusters but it's the final one that has a major reference fans will recognise. Obviously I'm going to spoil things massively if you read on so make that call and proceed accordingly.
Here's a picture of Dan Aykroyd looking bewildered to act as a distraction while you make your mind up.
The very final shot of the movie shows the team all set up in a new lab hard at work after saving the world. Leslie Jones' Patty Tolan character is running through a tape player previously referenced in an electronic voice phenomena related fart gag...
...suddenly, she looks up from the machine and says she thinks she's got something to the rest of the team. When they all look around she relays the word 'Zuul' to blank faces and shrugs.
If you're not up on your Ghostbuster's history then Zuul was the Gatekeeper, a demigod that possessed Sigourney Weaver's character in the original movie. It's probably not any sort of sequel hint though as the new Ghostbusters movie is full of easter eggs and references.
Directed by Paul Feig and starring Kristen Wiig, Melissa McCarthy, Kate McKinnon, Leslie Jones, and Chris Hemsworth. Ghostbusters is in cinemas now.
Images: Sony Pictures Entertainment