Warning: SPOILERS for Dexter: New Blood episode 4.
Dexter: New Blood features an emotional scene between Dexter and Deb that references the original series’ season 1 finale. Dexter: New Blood episode 4 puts together more of the puzzle pieces about Harrison’s Dark Passenger. As Harrison becomes involved with a stabbing at school, Dexter doubts his innocence, leading him down a path of self-reflection about his evolving Dark Passenger and changes since the original series, including a knowing call back to its conclusion.
Dexter: New Blood episode 4 features a chaotic premise in which Iron Lake’s high school closely evades a mass shooting, with Harrison being lauded as the teens’ savior. After realizing Ethan had plans to commit a mass murder at school, New Blood's Harrison claims that Ethan stabbed him with a knife before he was able to slice his friend’s leg and render him unconscious. Dexter begins to doubt Harrison’s story, largely due to his forensic background and details that don’t add up, leading him to go back to the school and recreate the story with Deb. Deb (as Dexter’s own conscience) then screams at her brother for doubting Harrison, imploring him to realize that he’s jealous because he always wanted to be celebrated as a hero.
When cartoonishly reminding Dexter of his own conflicted past, Deb reenacts Dexter’s vision from the original season 1 finale. Being reminded of his own long-gone wishes to be celebrated as a vigilante hero, not unlike being Miami’s Batman, Dexter envisions Deb as a crowd cheering his name, holding posters with his face on it, and celebrating him for keeping the city safe. This is a direct callback to Dexter’s season 1 finale, which followed Dexter having just murdered his brother, The Ice Truck Killer, and wishing others would celebrate him. The ending of season 1 showed Dexter envisioning himself walking through a crowd of fans, just like in New Blood episode 4, where they hold up posters of his face and thank him. New Blood’s Easter egg to Dexter season 1 even goes so far as to directly recreate an obscure poster that reads “Josie loves Dexter,” signaling this is the exact way Dexter has always dreamed of being celebrated for his murders.
Considering Deb is Dexter’s own conscience, it’s not surprising that she would berate him for being jealous of Harrison being lauded as a hero. While Dexter's original ending claimed that Dexter exiled himself to keep Harrison from turning out like him, there’s clearly a part of New Blood’s main serial killer that desperately hopes Harrison is like him. By doubting Harrison’s story about being the hero, Dexter was able to confirm that his son truly is like him, so maybe Dexter can be celebrated for taking out villains, too. Even back in Dexter season 1, he acknowledged that while he tells him the reason for his killing is to make sure there are less murders of innocent people, Dexter simply needed to satisfy his bloodthirsty urge. Telling himself a story that he was actually a hero saving innocent lives worked to give him a smaller sense of morality, but Dexter's season 1 dream proves he ultimately wishes he could just kill in the open while being praised for it.
Now that Dexter has confirmed Harrison has a Dark Passenger, he has a renewed sense of self-importance, not unlike in Dexter season 8 when he was tasked with teaching the code to Zach Hamilton. If he can’t be celebrated for his covert serial killing by the general public, he can at least be looked up to by the person who matters the most to him: Harrison. As Deb mocks Dexter for, the Morgans may now have some “sick serial killer family,” with Dexter passing on the Code of Harry to his teenage son. While the public won’t celebrate him as he fantasizes about in Dexter: New Blood, Dexter can at least be lauded as an inspirational hero by his son.