Disney’s “Incredibles 2” earned $180 million at the box office, making it the biggest opening ever for an animated movie.

But, there’s something moviegoers should know before heading to the theater to watch it, Disney has issued a seizure warning for the film.

The seizure warning involves a scene with a villain named “Screen-Slaver” that features a series of bright flashing lights.

The warning comes after some people posted concerns on social media that moviegoers with a type of epilepsy could be at risk.

The Epilepsy Foundation says in some situations flashing lights can trigger a seizure for about 3-percent of patients. It’s called photosensitive epilepsy and is more common in kids and teens.

A warning sign about flashing lights in the movie has been posted at some theaters. One sign was shared on social media. It was from Walt Disney Studios Motion Pictures and said:

“Dear Guests,
INCREDIBLES 2 contains a sequence of flashing lights which may affect customers who are susceptible to photosensitive epilepsy or other photosensitivities.