Warning: Spoilers ahead for Dark Matter episodes 1 & 2, plus information on the ending of the original novel, which could spoil the Apple TV+ adaptation.

Dark Matter includes the lesser-used plot device of the story’s protagonist also being the villain, showcasing both versions of Joel Edgerton’s Jason Dessen. Apple TV+’s multiversal adventure focuses largely on two separate realities, with Jason2 kidnapping the show’s “main” Jason and forcing him at gunpoint to trade lives. Despite looking identical, both Jasons have very different personalities, a change that was triggered by one specific instance in their shared past that was then driven forward by the life to which it led. Jason2’s motives are far from evil, but they’re certainly a sign of his selfishness and regret.

Because of the nature of the show’s narrative, several members of the Dark Matter cast are tasked with playing multiple roles. Although the actors are playing variations of their respective characters, the nuances in their performances need to be noticeable enough to tell the multiversal copies apart. As the production’s leading man, Edgerton perhaps needs to do this better than most, as his portrayal of the same man serving as hero and villain is what the saga is built upon. Thankfully, there aren’t many changes to Blake Crouch’s Dark Matter book when it comes to Jason Dessen’s TV counterparts.

Both Jasons in Dark Matter Have Experienced Different Lives

Joel Edgerton’s Dark Matter characters have different demeanors

Dark Matter is a tale of the road not taken, so both versions of Jason Dessen have lived lives based on different choices. Both characters are men of science, but how they chose to use their vast intellect depended on various circumstances and decisions that they made through the years. One of the biggest differences between the Jasons is their respective levels of scientific success.

Jason2, who kidnaps Jason in Dark Matter episode 1, “Are You Happy in Your Life?” is a renowned scientist who has earned the fictitious Pavia Prize for his breakthroughs in the study of superposition. The show also confirms Jason2 to be the co-founder of Velocity Laboratories. The other Jason, the story’s main character, stepped away from this field over a decade earlier than his counterpart. As a result, rather than the praise and the plaudits received by Jason2, Jason Dessen is a college professor in the other universe.

Jason2’s commitment to his work gave him enormous amounts of academic success, but his countless hours spent in a lab came at the expense of a personal life. As a result, Jason2 never had the chance to start a family. Inversely, the main Jason in Dark Matter is married with a teenage son but is not the decorated scientist he always aspired to be. As a result, both Jasons are resentful of some of their choices for taking from them what could have been.

The Path Of The Jasons Diverged When Daniela Became Pregnant With Charlie

Charlie doesn’t exist in Jason2’s universe

Charlie Dessen, Jason’s son, is 15 years old at the beginning of Dark Matter. While this may seem like a fairly arbitrary age, it actually marks the exact point when both Jasons stopped being the same man. The multiverse theory hinges on instances where an individual is presented with a choice, and the one they don’t make is also taken in another universe – which creates a new reality. For Jason Dessen, this pivotal moment was when Daniela informed him she was pregnant with their child.

The opposing points of view from both facets of Jason’s personality caused the reality to split in two. In one universe, Jason2 came into existence due to his unwillingness to step away from his research. In the other reality, Jason Dessen committed to being a family man, and Charlie was born. In short, in one universe, Jason and Daniela kept the baby; in the other, they didn’t.

The 15 years that followed were when Jason and Jason2 drifted further and further away from being the same man. Fatherhood caused certain changes in Jason, and Jason2’s scientific breakthroughs changed how his character grew. The main difference is that while both men wallowed in regret, only Jason2 had the resources to take action and find a universe where he chose to stay with Daniela and raise their son. Poetically, Jason2 wouldn’t have been able to travel the multiverse to correct his mistake if he hadn’t chosen to leave Daniela 15 years before.

Jason Dessen’s Marriage To Daniela Also Helped Shape His Character

Jason2 never married Daniela

Becoming a father isn’t the only thing that made the Jasons so different from one another. In one universe, Jason Dessen spends 15 years as a loving husband, which is something missing from Jason2’s past. Of course, Jason2 dated Daniela just as his counterpart had, but their courtship ended when it was decided they weren’t going to keep the baby. The main Jason is madly in love with his wife, and with the Dark Matter novel being written in first person from his perspective, the depth of that love is even easier to pick up on than in the show.

Jason2 never married after he and Daniela split up, and while the show establishes that he does live with Velocity colleague Amanda Lucas, their relationship doesn’t appear to be anywhere near as special as that of Jason and Daniela. It’s clear from Jason2’s decision to take his counterpart’s place that he has regretted his decision to leave Daniela for many years, and is taking his chance to rectify his error with both hands.

The Other Jasons In Dark Matter Are More Similar To The Main Jason Than Jason2

There are far more versions of Jason Dessen than just two

In the original Dark Matter novel, many more versions of Jason Dessen show up toward the end of the story. As Jason travels through the multiverse, he makes countless decisions that all create alternate realities that differ depending on his actions. As a result, the Jasons from these branched universes also start to try and find their way back to Daniela and Charlie, with many of them at least reaching the correct version of Chicago. What’s interesting about these other Jasons is that they’re very similar to the main character, as they’re versions of Jason from when he began his multiversal adventure.

So, up until Jason stepped into the box that takes him through the different realities, these variants didn’t exist. Instead, the other Jasons spawned as he made various choices during his journey, causing more realities to form. Some of the ensuing versions of Jason Dessen experienced more traumatic moments, and so are changed by the experience, but still have the same drive to return to Charlie and Daniela because of their intense love for the Dessen family. Jason2 never spent 15 years as a family man, so his experiences in Dark Matter differ greatly from those of his duplicates.