[1] The series explores a young Dexter Morgan, as he begins working as a forensic blood spatter analyst at the Miami Metro Police Department.
The episode received positive reviews from critics, who praised the performances, themes and character development, although many still expressed dissatisfaction with Spencer's motives.
The therapist, Paul Petrie, is content with Brian's progress, but warns him not to contact Dexter (Patrick Gibson).
While visiting Bobby (Reno Wilson), LaGuerta (Christina Milian) tells Harry (Christian Slater) that Barbara has been murdered, and he realizes Brian is responsible.
While checking the crime scene, Harry notices Brian in a nearby building, who is awaiting for Dexter's arrival.
Brian confronts Harry for not telling Dexter over his affair with Laura, and how forcing her to become an informant led to her death.
Spencer breaks into Becca's house and attacks her boyfriend Nelson, confronting her over lying to her about Nicky's true father.
Tanya (Sarah Michelle Gellar) informs Dexter that he has been approved to join forensics full-time, officially becoming part of Miami Metro.
Louis Peitzman of Vulture gave the episode a 3 star rating out of 5 and wrote, "At the risk of being branded a hater, it's clear to me that the series bit off more than it could chew.
To its credit, Original Sin has tried to stretch the limits of what a prequel can do, but as “Code Blues” reinforces, that's often at the expense of coherent plotting and basic logic.
"[7] Callum Murray of Game Rant wrote, "The explanation of his motive for killing his other victims feels a bit too rushed, and on the nose, but aside from that, the 10-minute opening sequence does a good job of setting up future events.
Overall, an entertaining final episode, and a promise of more action to come, but now it's all about Michael C. Hall's return in Resurrection this summer.
It expertly captured the feel of the original show and brilliantly cast returning and brand-new characters, resulting in one of the best Dexter seasons ever made.