The Mouse Guard movie is officially “dead.”

Director Wes Ball (The Maze Runner) confirmed the news late Tuesday night, having tried to keep the movie alive after Disney canceled the production at Fox. In lamenting the loss, Ball and one of his concept artists, Derek Zabrocki, revealed all the work that went into the development, from concept art to character molds to costumes to a previz video of what the motion-capture could’ve felt like.

Based on David Petersen Eisner-winning comic series, Mouse Guard was set up at Fox as a “Game of Thrones with mice” fantasy epic about a group of medieval mice sworn to protect their fellow rodents from all manner of dangers.

The proof-of-concept demo reel, what Ball calls a “very good looking previz, with environments capable of streaming live to stage during motion capture with our actors,” shows members of the guard riding on the backs of birds, facing down a venomous snake, witnessing the beauty of behemoth tortoises, and in the throws of heated combat.

Credit: Wes Ball /YouTube

“While the visual quality is impressive, it’s important to note this is only meant to illustrate how the movie will ‘feel’ not how it will ‘look,'” Ball clarified. “Everything will ultimately be sent to WETA Digital to be recreated with cutting-age photorealistic CG.”

Idris Elba, Andy Serkis, and Thomas Brodie-Sangster were among those attached to star in Mouse Guard, but, in light of Disney’s acquisition of Fox, the film was canceled two weeks prior to the start of shooting. Deadline reported the studio re-evaluated Mouse Guard and determined it was no longer a “good fit” for its new movie slate.

EW learned at the time that the rights reverted back to the producers, who attempted to find a new home for the project. Ball confirmed on Tuesday night in a tweet, showcasing even more work, “Yes sadly, its true. Our #mouseguard movie is dead. Seems it’s too big a risk. It’s a damn shame really. We had something special. To my hella talented cast/crew: I’m sorry I couldn’t push this one through. The past year with you all has been a blast. May the Guard prevail!”

The demo reel took “about 12 weeks” for the teams of Halon and Fox VFX labs to create, according to Ball. Zabrocki, meanwhile, shared pieces on Instagram of “hundreds” of concept art designs he illustrated for the film.

“We had so much fun since the project was so free to interpreting that let us go crazy with world and look of it,” he wrote.

See more illustrations below.

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