As The Revenant heads into its first weekend in theaters after scoring a leading 12 Oscar nominations, there's a lot of curiosity around how director Alejandro González Iñárritu and his team filmed some of the movie's more daring sequences. First there's the incredible bear attack, which Iñárritu is still trying to keep secret, though we know it was pulled off with a combination of camera tricks and star Leonardo DiCaprio rigged up to a pulley system.

And in this new video via the New York Times' Anatomy of a Scene, we listen in as Iñárritu narrates another of the film's more difficult sequences involving DiCaprio's Hugh Glass' attempt to escape from the brutal Arikara tribe in frigid rough waters without being detected. Here Iñárritu describes the difficulty of filming the sequence in two separate locations, as well as his desire to shoot part of it in one long take.

Check it out.

After watching the video, you can see why Leonardo DiCaprio is the front-runner to win this year's Best Actor Oscar. Not only was it an incredibly physical performance, but much of Glass' struggles were solitary ones and relied on DiCaprio conveying all of the character's hopes and fears without much dialogue at all. 

The Revenant did change some things from the real-life story of Hugh Glass. While his incredible journey post-bear attack is all real, some of the characters, events and the final outcome are different. You can read more about that in this fascinating account of the true story behind The Revenant, as told in 1939, via Time.