The following contains spoilers for Indiana Jones and the Dial of Destiny, in theaters now.

Indiana Jones and the Dial of Destiny has tremendous fun with the series' history. The fifth film in the action-adventure franchise brings back plenty of Indy's old friends while introducing fresh rivals. One major addition to the series is absent from the movie, however -- and there's a very good reason for that.

Dial of Destiny reveals that Shia Labeouf's Mutt Williams -- the son of Indy who introduced in the prior film -- has died off-screen. While it's a sad twist of fate for a character who seemed poised to follow in his father's footsteps, his death benefits the overall bittersweet tone of the film. Mutt's passing adds extra layers to the first and third acts of the movie through a blunt, emotional reveal.

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What Happens to Mutt in Indiana Jones and the Dial of Destiny

Indy and Mutt (Shia Labeouf) in Indiana Jones and the Kingdom of the Crystal Skull

Mutt was one of the main characters of Indiana Jones and the Kingdom of the Crystal Skull. Introduced as the rebellious son of Marion Ravenwood and deceased pilot Colin Williams, he attempted to locate his mother after family friend Professor Oxley brought him into the orbit of Indiana Jones. The two men constantly conflicted with one another, especially after they discovered that Indiana was actually Henry's father. But working together, they were able to save Marion and Oxley, while also thwarting the intentions of Soviet agents after the Crystal Skull.

Indiana Jones 4 ended with Mutt on good terms with his parents, happily attending their long-postponed wedding. But it seems that the tension between Indiana and Mutt never fully diminished. As Indiana explains to the newly introduced Helena Shaw in Indiana Jones and the Dial of Destiny, their relationship remained uneasy for years, and Mutt joined the army after a particularly rough patch with his father. He then found himself deployed into combat -- presumably the Vietnam War, since the film takes place primarily in 1969 -- and Mutt was tragically killed in the line of duty. This proved to be too great of an emotional blow to Indy and Marion, leading to their divorce. Dial of Destiny opens with Indy still mourning the loss of his son and left alone to wallow in his grief as his retirement approaches.

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Why Mutt Needed To Die in Dial of Destiny

Harrison Ford in Indiana Jones and the Dial of Destiny poster

Mutt's fate is a tragic one, even if the character has remained controversial within the fan base ever since Indiana Jones 4 premiered in 2008. Mutt was an interesting foil in theory -- the young rebel to Indy's stuffy teacher. But the film had trouble balancing Mutt's personality quirks with his emotional arc. The character was also at the center of some of Crystal Skull's more lackluster moments, including a much-maligned sequence of Mutt swinging on vines alongside a horde of monkeys. By contrast, Helena is a more compelling and fitting foil to Indiana; her skills match his, but her motivations are the polar opposite.

Dial of Destiny director James Mangold said there wasn't room for Mutt alongside Helena in the fifth movie. Given that, the film's decision to use his death as a fundamental piece of Indiana's character growth -- or lack thereof -- is a good use of the character. Indiana's decision to quietly isolate himself feels more authentic and earned. His split with Marion, especially after the way their relationship had been fulfilled in the previous film, carries a far greater weight since viewers know that it stemmed from a truly tragic circumstance. That, in turn, makes their reunion more effective, infusing it with an older and lived-in vibe that extols the film's central theme: history remains important.

Mutt's death makes perfect sense, even within the greater context of the Indiana Jones franchise. It serves as a clever way to build on the themes of wartime in the previous films. Raiders of the Lost Ark, The Last Crusade and the beginning of Dial of Destiny all take place during World War II and indulge in some rip-roaring action and adventure -- befitting the big and bombastic way that conflict can often be portrayed in media. But the Vietnam War is regarded in a far harsher light, and Indiana's heartbreak over Mutt's fate speaks to the disillusionment of an iconic Nazi-punching hero. Dial of Destiny makes the most out of Mutt's disappearance, no matter fans' feelings toward the character.

Indiana Jones and the Dial of Destiny is in theaters now.