Chris Pratt posted a short video to his Instagram today, revealing a mysterious ice cave that leads somewhere quite unexpected, the actor believes. Pratt, a goofy everyman who just happens to be a megastar, is in Iceland filming The Tomorrow WarThe sci-fi actioner, formerly titled Ghost Draft, boasts an ensemble cast including Yvonne Strahovski, Mary Lynn Rajskub, Sam Richardson, Betty Gilpin, Edwin Hodge, and the incomparable J.K. Simmons, who appears in the video sporting a beard as white as an Icelandic winter.

Directed by The Lego Batman films’ Chris McKay, little is known about the plot of the movie other than it being about a man (Pratt?) drafted to fight a war with pretty big stakes. In fact, all of humanity hangs in the balance, unless he’s able to appropriately confront the past. What all of that means is anyone’s guess.

Pratt, the star of the Jurassic World franchise, is executive producing the film—the first time he’s done so—from a script written by Zach Dean (24 Hours to Live). The potential blockbuster is due for release on Christmas day, 2020. It joins a growing list of big movies to be shot in Iceland, known for its spectacular landscapes, glaciers, and volcanoes. Among them, Interstellar, Noah, Batman Begins, Prometheus, Star Trek Into Darkness, Star Wars: The Force Awakens, and Rogue One: A Star Wars Story.

It’s worth noting that finding a Hollywood actor who moonlights as a geologist is extraordinarily rare. And almost none take on side gigs as glaciologists anymore. Therefore, a topographically guided tour from a star of the silver screen is liable to result in a litany of misinformation. Production of this film has seen Pratt flexing his exploration muscles, but he might want to engage with a cartographer before making any future geographical affirmations.

In any event, you can watch his silly video below.