When Jumanji: Welcome to the Jungle premiered in 2017, it proved to be a surprisingly  popular and successful blockbuster. The film made over $961 million worldwide and showed that audiences were receptive to the re-imagining of the 1995 film.

Now, Karen Gillan, who plays Ruby Roundhouse in the film, recently posted a picture of herself and co-star Jack Black to Instagram, offering fans another look behind the scenes of the film's untitled sequel.

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Gillan writes that 'Ruby and Shelley back in the game', referring to Gillan and Black's respective characters in the series, Ruby Roundhouse and Professor Sheldon "Shelly" Oberon.

Jumanji: Welcome to the Jungle followed four teenagers who were sucked into a video game jungle and had to survive, work together, and fight their way out in order to return to their normal lives. Gillan and Black play two of the teenager's avatars within the game, and they'll presumably play those same roles in the sequel.

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While the follow up to Jumanji: Welcome to the Jungle does not yet have a title, principal production on the film has entered its fourth month. In addition to Gillan and Black, Jumanji: Welcome to the Jungle stars Dwayne Johnson and Kevin Hart will reprise their roles alongside franchise newcomers Awkwafina and Danny DeVito.

The Jumanji sequel will hit theaters on December 13. Jake Kasdan returns to direct the movie, which stars Dwayne Johnson, Kevin Hart, Jack Black, Karen Gillan, Danny DeVito, Danny Glover, Alex Wolff, Ser’Darius Blain, Madison Iseman and Morgan Turner.