The BDSM-themed movie "Fifty Shades of Grey" and its sequel "Fifty Shades Darker" just broke records for being the most successful 18-rated movie in the UK. The sequel just started airing four weeks ago, but it has already earned over 20 million pounds.

Metro UK reports that the first movie in the franchise, "Fifty Shades of Grey" earned 35 million when it was released last Valentine's Day 2015. Other movies that made it to the list include Leonardo Dicaprio's "The Wolf of Wall Street" for third place, "Gone Girl" and "Hannibal" round up the top five.

The movies are based on the best-selling novels written by E.L. James. The plot of the movies and the books centers on the character of Anastasia Steele, who at the beginning of the book, is a college student. She meets Christian Grey and the two go on to have a relationship. Grey enjoys BDSM and he has Anastasia sign an agreement to be his submissive. Conflicts arise between the couple as their lifestyles are too different from each other.

While the novels and film were well-received by the public, there are critics who continue to bash them. But despite this, the main actors in the film, Jamie Dornan and Dakota Johnson have garnered immense popularity due to their portrayal of the titular characters.

E Online News reports that Johnson claimed that after playing Anastasia Steele on "Fifty Shades of Grey" and "Fifty Shades Darker," she can confidently say that she has changed as an actress. She tags her portrayal as an educational experience and says that she has grown up after playing the part.

Meanwhile, the last installment of the movie franchise, "Fifty Shades Freed," will be shown by next year. It was filmed back to back with the previous movie and will conclude the love story of Ana Steele and Christian Grey.