Dexter's Frank Lundy Secret Is The Show's First Big Mistake
The later seasons of Dexter were nowhere near as good as the first, and FBI agent Frank Lundy was actually the secret beginning of the show's downfall.

As the original eight-season run draws to a close, things for the beloved thriller series Dexter take a turn for the worse. Unfortunately for Dexter Morgan (Michael C. Hall), a vigilante serial killer torn between his "Dark Passenger" and the impulses of "Harry's Moral Code," the story ends abruptly And not as expected. Dexter ultimately escaped trial for his crimes as the Bay Harbor Butcher, while his son and girlfriend fled in the other direction together. Also, the finale included the tragic death of Dexter's adopted sister, Debra Morgan (Jennifer Carpenter), after Dexter mercifully shut off her life support system. However, a big reason the ending was so underwhelming actually goes back to the seasons before Dexter's finale, when the show made its first big mistake.
Dexter's season 4 saw the death of Agent Frank Lundy (Keith Carradine), a plot point that secretly marked the beginning of the show's slow decline. Lundy appeared in Season 2 as an investigator in the Bayhaven Butcher case. At some point, he almost discovers that Dexter Morgan, Miami Metro's exclusive blood spatter analyst, is the prolific serial killer he's hunting. However, Dexter managed to throw him Off track, Lundy's most important relationship is with Debra instead. Despite an approximate 30-year age difference, Debra and Lundy have developed a strong romantic relationship. That's because the connection was so important that killing the character actually represented a major blunder for the series, reducing Lundy to an emotional anchor for beating Debra instead of providing some much-needed support for a key character. support.
Why Frank Lundy's Death Was A Dexter Mistake

At the end of Dexter season 2, Lundy and Debra were forced to break off their relationship as the Bay Harbor Butcher case was closed and Lundy continued his career. Lundy became Debra's source of comfort and safety after the trauma of dating and being kidnapped by the Ice Truck Killer in season 1. His leaving is just another heartbreak for her to deal with. Lundy reappeared in Season 4 to continue his long hunt for the notorious and mysterious Trinity Killer, and all was well for the couple until they were both shot dead by the Trinity Killer's daughter in episode four. Debra survived the shooting, but the loss of Lundy turned the character into another source of grief rather than strength and He could have been comforted. Ultimately, this treatment became the defining sign of Dexter's late-season failure.
How Lundy's Death Set Up Dexter's Failure

Many viewers felt that Lundy should have had a more meaningful ending, and that his death marked the first of an unfortunate trend of unsatisfying and rushed character arcs, which continued to be criticized in Dexter's finale. After Lundy's death, things only got worse for Debra. More loved ones died beside her, including her sister-in-law Rita. Additionally, she faces a state of emotional depression, which leads Debra to confess her love to Dexter, the only stable presence in her life. She even became a killer herself, shooting Captain LaGuerta to protect Dexter after discovering Dexter's secret. As Dexter entered its final season, Debra was clearly overwhelmed by all the trauma she faced, despite having resumed dating and being promoted to lieutenant. Her character lacks the strong sense of direction she's had at the start of previous seasons, which only adds to the confusion and rush of season eight.
Lundy's death had a profound effect on other characters as well. In the revived series, Dexter: New Blood, it is implied that Dexter felt guilty about Lundy's death, despite his irresponsible. The guilt likely actually stems from Debra being his new Dark Passenger, so Dexter is forced to live with the trauma of her former lover's death. While Debra was a strong character, Lundy's death weighed on her more than anything else, and neither the character nor Dexter fully recovered from that plot choice.