A trailer has been released for the upcoming film Mowgli, promoting it as the “darkest telling” of Rudyard Kipling’s The Jungle Book ever put to film.

Originally published in 1894, the story, about a human boy named Mowgli who was raised by wolves in the jungles of India, has been put to film several times. Most famously it was adapted by Disney, first as an animated movie in 1967, and then remade in live-action and CGI in 2016. Those versions are by the far the ones most familiar to the popular consciousness, but are also very loose adaptations with a much more lighthearted tone than the source material.

Enter Andy Serkis, famous for his motion-capture CGI, who wanted to make a more faithful telling. The fact that it is rated PG-13 is one sign that this will be a less family-friendly film, and the images from the trailer help reinforce that, with a general use of darker colors and a rougher appearance on the CGI animals; the man-eating tiger Shere Khan (Benedict Cumberbatch), for example, has numerous scars, as well as the crippled front paw that he sported in the book.

The trailer also shows scenes of Mowgli, played here by Rohan Chand, kept in a cage at some points; in others, there are discussions about whether he should be considered a man or an animal, with Mowgli himself at one point saying that he is neither. This implies a greater focus on his sense of identity than in other versions of this story.

Other parts include the bear Baloo, played by Serkis himself, and the panther Bagheera, played by Christian Bale; both serve as mentors for Mowgli. His adoptive wolf mother, Nashi, will be played by Naomie Harris, while the snake Kaa, in an unusual move, will be changed into a female played by Cate Blanchett. “She” is seen at the end of the trailer and comes off as rather threatening, though she may turn out to be Mowgli’s ally, as in the book.

This movie will be rather different than the 2016 Disney film, but the basic stories are the same; will that hinder audience interest? The darker tone may also prove a problem, because, even if this version is closer to the original novel, fans may simply see it as a “darker and grittier” take on what they consider a lighthearted story.