Michael C. Hall, who played the titular antihero in the main series, serves as the narrator of the prequel. Patrick Gibson plays Dexter in his late teens as a young assassin in training, fifteen years before the events of the original Dexter series.

Set in Miami in 1991, the ten-episode drama follows Dexter (Patrick Gibson), a college student honing his killing skills with the help and support of his adoptive father, Harry (Christian Slater). With his father, he finds solace and understanding, especially as his bloodthirsty desires grow and can no longer be ignored.
As his only confidant, Harry teaches Dexter a code designed to help him find and kill people who deserve to die—all while avoiding capture by law enforcement. This presents a particular challenge for the young Dexter as he begins a forensics internship with the Miami Metro Police Department.
The first season also stars Molly Brown, Christina Milian, James Martinez, Alex Shimizu, Reno Wilson, Sarah Michelle Gellar and Patrick Dempsey.
Phillips, who served as showrunner on the first four seasons of Dexter, is currently producing Dexter: Resurrection, a sequel to the limited series Dexter: New Blood, which premieres this summer. The Dexter universe is now one step closer to adding a second spin-off prequel series to the franchise, the long-rumored limited series Trinity Killer, starring John Lithgow, who originally played the deranged killer, who may return to narrate.