The sequel of the 2013 animated hit, Frozen, is reportedly in the works. Though little is known about the movie, reports are suggesting that a darker plot will feature.

Upon its release on Thanksgiving season 2013, Frozen became one of the most-watched Disney animated features of all-time. Grossing $1,274,219,009 in worldwide sales, the movie also became the highest-grossing animated film of all time, and a sequel is indeed something that its fans are looking forward to seeing.

In a past report, lead star Idina Menzel said that the sequel is already "in the works," as well as a musical inspired by the movie.

According to several reports, the plot of the second film will adapt the orginal Hans Christian Anderson fairy tale called "The Snow Queen," and it could result in a darker story line. In the story, the protagonist Gerda, chooses between good and evil. In the land where the story happens, a troll creates a mirror that shows the evil or bad in everything. Gerta's close friend, Kai, unfortunately finds the magical yet dangerous mirror and becomes evil herself from staring into the mirror many times.

Kai is then taken by the queen of the kingdom and was forced to forget about Gerda. Gerda, being a true friend, searches for Kai in order to save him. Gerda reaches the Snow Queen's palace and finds Kai, and gives him a kiss to break the Queen's spell.

"The Snow Queen" is easily one of Andersen's most famous stories, and has been published and transcribed in many languages all over the world. The first Frozen film was derived from this story as well, starring Princess Anna who goes on an adventure to save her sister, Queen Elsa, who ran away because of her magical powers.