S**t. We’d better stock up on tinned butter beans and thick socks; we might be down here for a while. A study released in the December edition of Pediatrics states that PG-13 films feature gun violence 2.6 times-an-hour, which is way more than R-rated films.

Liam NeesonLiam Neeson holding a gun on someone, and not even in a film

This means the ratings are a bit off, probably. But it could mean an army of 12-year-olds – clad in Finding Nemo pyjamas - will take to the streets armed to the nines with the most advanced weaponry known to western civilisation. As law-abiding citizens, we just have to hope it doesn’t come to that.

“Most parents would be horrified to learn that the very films that target young people are the ones with the most violence" said Brad Bushman, a professor of communication and psychology of the Ohio State University who has no problem with the overuse of the word ‘horrified’. He’s also the study's lead author.

"Parents rely on these ratings to make decisions about that is appropriate for their children," he added. “It’s disturbing that PG-13 movies are filled with so much gun violence,” said Dan Romer, director of the Adolescent Communication Institute of the Annenberg Public Policy Center (APPC) and a co-author of the study.

“We know that movies teach children how adults behave, and they make gun use appear exciting and attractive.”

Back in 2009, both PG and R-rated films contained a similar amount of violence, but then The Avengers, The Amazing Spiderman and Taken 2 were all liberally handed PG ratings. This drove up the levels of gun violence in PG films, and now we’re just left with a post-apocalyptic world of film ratings, where no one knows good from evil and evil gangs preside over valuable commodities like leather and golden syrup.

What should you do? Just chill out. Watch World War Z or something. But not with your kids: zombies head-butt cars just to get in and eat raw human flesh.