Under the Motion Picture Association rating system, R stands for Restricted. That means anybody under 17 has to be accompanied by a parent or adult guardian because the movie contains adult material. That translates into harsh language, intense violence, sexually oriented nudity, drug abuse, etc.

Of course, some people want to see movies that feature violence — what war movie doesn’t? — and lots of outstanding urban dramas feature bad language and drug abuse. But having these certainly doesn’t make a movie good and some R-rated movies are so bad people under 17 should be thankful they can’t see them alone.

24/7 Tempo’s list of the worst R-rated movies ever made contains several movies you probably haven’t heard of — movies that were so bad they were released and quickly disappeared without ever entering the public’s consciousness. Some of them have actors you’ve heard of, but none of them have A-list directors like Steven Spielberg or Martin Scorsese. Sometimes bad movies become cult favorites, but these movies are just plain bad. Enjoy!

And if these aren’t bad enough, try the 25 worst movies of all time.

Click here to see the worst R-rated movies ever made

To determine the 15 worst R-rated movies of all time, 24/7 Tempo reviewed data from the Internet Movie Database (IMDb) and Rotten Tomatoes. We created an index based on the average critic rating from Rotten Tomatoes, the average audience rating from Rotten Tomatoes, and the average user rating from IMDb. We only considered feature films with at least 5,000 Rotten Tomatoes audience reviews, 10 Rotten Tomatoes critic reviews, and 10,000 IMDb user reviews. All data is for the most recent period available. Data was collected February 2021.